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3,053
Classifying Triangles by Lengths
Easy
<p>Table: <font face="monospace"><code>Triangles</code></font></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | A | int | | B | int | | C | int | +-------------+------+ (A, B, C) is the primary key for this table. Each row include the lengths of each of a triangle&#39;s three sides. </pre> <p>Write a query to find the type of <strong>triangle</strong>. Output one of the following for each row:</p> <ul> <li><strong>Equilateral</strong>: It&#39;s a triangle with <code>3</code> sides of equal length.</li> <li><strong>Isosceles</strong>: It&#39;s a triangle with <code>2</code> sides of equal length.</li> <li><strong>Scalene</strong>: It&#39;s a triangle with <code>3</code> sides of differing lengths.</li> <li><strong>Not A Triangle: </strong>The given values of <code>A</code>, <code>B</code>, and <code>C</code> don&#39;t form a triangle.</li> </ul> <p>Return <em>the result table in <strong>any order</strong></em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Triangles table: +----+----+----+ | A | B | C | +----+----+----+ | 20 | 20 | 23 | | 20 | 20 | 20 | | 20 | 21 | 22 | | 13 | 14 | 30 | +----+----+----+ <strong>Output:</strong> +----------------+ | triangle_type | +----------------+ | Isosceles | | Equilateral | | Scalene | | Not A Triangle | +----------------+ <strong>Explanation:</strong> - Values in the first row from an Isosceles triangle, because A = B. - Values in the second row from an Equilateral triangle, because A = B = C. - Values in the third row from an Scalene triangle, because A != B != C. - Values in the fourth row cannot form a triangle, because the combined value of sides A and B is not larger than that of side C.</pre>
Database
SQL
# Write your MySQL query statement below SELECT CASE WHEN A + B <= C OR A + C <= B OR B + C <= A THEN 'Not A Triangle' WHEN A = B AND B = c THEN 'Equilateral' WHEN (A = B) + (B = C) + (A = C) = 1 THEN 'Isosceles' ELSE 'Scalene' END AS triangle_type FROM Triangles;
3,054
Binary Tree Nodes
Medium
<p>Table: <font face="monospace"><code>Tree</code></font></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | N | int | | P | int | +-------------+------+ N is the column of unique values for this table. Each row includes N and P, where N represents the value of a node in Binary Tree, and P is the parent of N. </pre> <p>Write a solution to find the node type of the Binary Tree. Output one of the following for each node:</p> <ul> <li><strong>Root</strong>: if the node is the root node.</li> <li><strong>Leaf</strong>: if the node is the leaf node.</li> <li><strong>Inner</strong>: if the node is neither root nor leaf node.</li> </ul> <p>Return <em>the result table ordered by node value in <strong>ascending order</strong></em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Tree table: +---+------+ | N | P | +---+------+ | 1 | 2 | | 3 | 2 | | 6 | 8 | | 9 | 8 | | 2 | 5 | | 8 | 5 | | 5 | null | +---+------+ <strong>Output:</strong> +---+-------+ | N | Type | +---+-------+ | 1 | Leaf | | 2 | Inner | | 3 | Leaf | | 5 | Root | | 6 | Leaf | | 8 | Inner | | 9 | Leaf | +---+-------+ <strong>Explanation:</strong> - Node 5 is the root node since it has no parent node. - Nodes 1, 3, 6, and 9 are leaf nodes because they don&#39;t have any child nodes. - Nodes 2, and 8 are inner nodes as they serve as parents to some of the nodes in the structure. </pre> <p>&nbsp;</p> <p><strong>Note:</strong> This question is the same as <a href="https://leetcode.com/problems/tree-node/description/" target="_blank"> 608: Tree Node.</a></p>
Database
SQL
# Write your MySQL query statement below SELECT DISTINCT t1.N AS N, IF(t1.P IS NULL, 'Root', IF(t2.P IS NULL, 'Leaf', 'Inner')) AS Type FROM Tree AS t1 LEFT JOIN Tree AS t2 ON t1.N = t2.p ORDER BY 1;
3,055
Top Percentile Fraud
Medium
<p>Table: <code>Fraud</code></p> <pre> +-------------+---------+ | Column Name | Type | +-------------+---------+ | policy_id | int | | state | varchar | | fraud_score | int | +-------------+---------+ policy_id is column of unique values for this table. This table contains policy id, state, and fraud score. </pre> <p>The Leetcode Insurance Corp has developed an ML-driven <strong>predictive model </strong>to detect the <strong>likelihood</strong> of fraudulent claims. Consequently, they allocate their most seasoned claim adjusters to address the top <code>5%</code> of <strong>claims</strong> <strong>flagged</strong> by this model.</p> <p>Write a solution to find the top <code>5</code> <strong>percentile</strong> of claims from <strong>each state</strong>.</p> <p>Return <em>the result table ordered by </em><code>state</code><em> in <strong>ascending</strong> order, </em><code>fraud_score</code><em> in <strong>descending</strong> order, and </em><code>policy_id</code><em> in <strong>ascending</strong> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Fraud table: +-----------+------------+-------------+ | policy_id | state | fraud_score | +-----------+------------+-------------+ | 1 | California | 0.92 | | 2 | California | 0.68 | | 3 | California | 0.17 | | 4 | New York | 0.94 | | 5 | New York | 0.81 | | 6 | New York | 0.77 | | 7 | Texas | 0.98 | | 8 | Texas | 0.97 | | 9 | Texas | 0.96 | | 10 | Florida | 0.97 | | 11 | Florida | 0.98 | | 12 | Florida | 0.78 | | 13 | Florida | 0.88 | | 14 | Florida | 0.66 | +-----------+------------+-------------+ <strong>Output:</strong> +-----------+------------+-------------+ | policy_id | state | fraud_score | +-----------+------------+-------------+ | 1 | California | 0.92 | | 11 | Florida | 0.98 | | 4 | New York | 0.94 | | 7 | Texas | 0.98 | +-----------+------------+-------------+ <strong>Explanation</strong> - For the state of California, only policy ID 1, with a fraud score of 0.92, falls within the top 5 percentile for this state. - For the state of Florida, only policy ID 11, with a fraud score of 0.98, falls within the top 5 percentile for this state. - For the state of New York, only policy ID 4, with a fraud score of 0.94, falls within the top 5 percentile for this state. - For the state of Texas, only policy ID 7, with a fraud score of 0.98, falls within the top 5 percentile for this state. Output table is ordered by state in ascending order, fraud score in descending order, and policy ID in ascending order. </pre>
Database
SQL
# Write your MySQL query statement below WITH T AS ( SELECT *, RANK() OVER ( PARTITION BY state ORDER BY fraud_score DESC ) AS rk FROM Fraud ) SELECT policy_id, state, fraud_score FROM T WHERE rk = 1 ORDER BY 2, 3 DESC, 1;
3,056
Snaps Analysis
Medium
<p>Table: <code>Activities</code></p> <pre> +---------------+---------+ | Column Name | Type | +---------------+---------+ | activity_id | int | | user_id | int | | activity_type | enum | | time_spent | decimal | +---------------+---------+ activity_id is column of unique values for this table. activity_type is an ENUM (category) type of (&#39;send&#39;, &#39;open&#39;). This table contains activity id, user id, activity type and time spent. </pre> <p>Table: <code>Age</code></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | user_id | int | | age_bucket | enum | +-------------+------+ user_id is the column of unique values for this table. age_bucket is an ENUM (category) type of (&#39;21-25&#39;, &#39;26-30&#39;, &#39;31-35&#39;). This table contains user id and age group.</pre> <p>Write a solution to calculate the <strong>percentage</strong> of the total time spent on <strong>sending</strong> and <strong>opening snaps</strong> for <strong>each age group</strong>. Precentage should be <strong>rounded</strong> to <code>2</code> decimal places.</p> <p>Return <em>the result table </em><em>in <strong>any</strong> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Activities table: +-------------+---------+---------------+------------+ | activity_id | user_id | activity_type | time_spent | +-------------+---------+---------------+------------+ | 7274 | 123 | open | 4.50 | | 2425 | 123 | send | 3.50 | | 1413 | 456 | send | 5.67 | | 2536 | 456 | open | 3.00 | | 8564 | 456 | send | 8.24 | | 5235 | 789 | send | 6.24 | | 4251 | 123 | open | 1.25 | | 1435 | 789 | open | 5.25 | +-------------+---------+---------------+------------+ Age table: +---------+------------+ | user_id | age_bucket | +---------+------------+ | 123 | 31-35 | | 789 | 21-25 | | 456 | 26-30 | +---------+------------+ <strong>Output:</strong> +------------+-----------+-----------+ | age_bucket | send_perc | open_perc | +------------+-----------+-----------+ | 31-35 | 37.84 | 62.16 | | 26-30 | 82.26 | 17.74 | | 21-25 | 54.31 | 45.69 | +------------+-----------+-----------+ <strong>Explanation:</strong> For age group 31-35: - There is only one user belonging to this group with the user ID 123. - The total time spent on sending snaps by this user is 3.50, and the time spent on opening snaps is 4.50 + 1.25 = 5.75. - The overall time spent by this user is 3.50 + 5.75 = 9.25. - Therefore, the sending snap percentage will be (3.50 / 9.25) * 100 = 37.84, and the opening snap percentage will be (5.75 / 9.25) * 100 = 62.16. For age group 26-30: - There is only one user belonging to this group with the user ID 456. - The total time spent on sending snaps by this user is 5.67 + 8.24 = 13.91, and the time spent on opening snaps is 3.00. - The overall time spent by this user is 13.91 + 3.00 = 16.91. - Therefore, the sending snap percentage will be (13.91 / 16.91) * 100 = 82.26, and the opening snap percentage will be (3.00 / 16.91) * 100 = 17.74. For age group 21-25: - There is only one user belonging to this group with the user ID 789. - The total time spent on sending snaps by this user is 6.24, and the time spent on opening snaps is 5.25. - The overall time spent by this user is 6.24 + 5.25 = 11.49. - Therefore, the sending snap percentage will be (6.24 / 11.49) * 100 = 54.31, and the opening snap percentage will be (5.25 / 11.49) * 100 = 45.69. All percentages in output table rounded to the two decimal places. </pre>
Database
Python
import pandas as pd def snap_analysis(activities: pd.DataFrame, age: pd.DataFrame) -> pd.DataFrame: merged_df = pd.merge(activities, age, on="user_id") total_time_per_age_activity = ( merged_df.groupby(["age_bucket", "activity_type"])["time_spent"] .sum() .reset_index() ) pivot_df = total_time_per_age_activity.pivot( index="age_bucket", columns="activity_type", values="time_spent" ).reset_index() pivot_df = pivot_df.fillna(0) pivot_df["send_perc"] = round( 100 * pivot_df["send"] / (pivot_df["send"] + pivot_df["open"]), 2 ) pivot_df["open_perc"] = round( 100 * pivot_df["open"] / (pivot_df["send"] + pivot_df["open"]), 2 ) return pivot_df[["age_bucket", "send_perc", "open_perc"]]
3,056
Snaps Analysis
Medium
<p>Table: <code>Activities</code></p> <pre> +---------------+---------+ | Column Name | Type | +---------------+---------+ | activity_id | int | | user_id | int | | activity_type | enum | | time_spent | decimal | +---------------+---------+ activity_id is column of unique values for this table. activity_type is an ENUM (category) type of (&#39;send&#39;, &#39;open&#39;). This table contains activity id, user id, activity type and time spent. </pre> <p>Table: <code>Age</code></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | user_id | int | | age_bucket | enum | +-------------+------+ user_id is the column of unique values for this table. age_bucket is an ENUM (category) type of (&#39;21-25&#39;, &#39;26-30&#39;, &#39;31-35&#39;). This table contains user id and age group.</pre> <p>Write a solution to calculate the <strong>percentage</strong> of the total time spent on <strong>sending</strong> and <strong>opening snaps</strong> for <strong>each age group</strong>. Precentage should be <strong>rounded</strong> to <code>2</code> decimal places.</p> <p>Return <em>the result table </em><em>in <strong>any</strong> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Activities table: +-------------+---------+---------------+------------+ | activity_id | user_id | activity_type | time_spent | +-------------+---------+---------------+------------+ | 7274 | 123 | open | 4.50 | | 2425 | 123 | send | 3.50 | | 1413 | 456 | send | 5.67 | | 2536 | 456 | open | 3.00 | | 8564 | 456 | send | 8.24 | | 5235 | 789 | send | 6.24 | | 4251 | 123 | open | 1.25 | | 1435 | 789 | open | 5.25 | +-------------+---------+---------------+------------+ Age table: +---------+------------+ | user_id | age_bucket | +---------+------------+ | 123 | 31-35 | | 789 | 21-25 | | 456 | 26-30 | +---------+------------+ <strong>Output:</strong> +------------+-----------+-----------+ | age_bucket | send_perc | open_perc | +------------+-----------+-----------+ | 31-35 | 37.84 | 62.16 | | 26-30 | 82.26 | 17.74 | | 21-25 | 54.31 | 45.69 | +------------+-----------+-----------+ <strong>Explanation:</strong> For age group 31-35: - There is only one user belonging to this group with the user ID 123. - The total time spent on sending snaps by this user is 3.50, and the time spent on opening snaps is 4.50 + 1.25 = 5.75. - The overall time spent by this user is 3.50 + 5.75 = 9.25. - Therefore, the sending snap percentage will be (3.50 / 9.25) * 100 = 37.84, and the opening snap percentage will be (5.75 / 9.25) * 100 = 62.16. For age group 26-30: - There is only one user belonging to this group with the user ID 456. - The total time spent on sending snaps by this user is 5.67 + 8.24 = 13.91, and the time spent on opening snaps is 3.00. - The overall time spent by this user is 13.91 + 3.00 = 16.91. - Therefore, the sending snap percentage will be (13.91 / 16.91) * 100 = 82.26, and the opening snap percentage will be (3.00 / 16.91) * 100 = 17.74. For age group 21-25: - There is only one user belonging to this group with the user ID 789. - The total time spent on sending snaps by this user is 6.24, and the time spent on opening snaps is 5.25. - The overall time spent by this user is 6.24 + 5.25 = 11.49. - Therefore, the sending snap percentage will be (6.24 / 11.49) * 100 = 54.31, and the opening snap percentage will be (5.25 / 11.49) * 100 = 45.69. All percentages in output table rounded to the two decimal places. </pre>
Database
SQL
# Write your MySQL query statement below SELECT age_bucket, ROUND(100 * SUM(IF(activity_type = 'send', time_spent, 0)) / SUM(time_spent), 2) AS send_perc, ROUND(100 * SUM(IF(activity_type = 'open', time_spent, 0)) / SUM(time_spent), 2) AS open_perc FROM Activities JOIN Age USING (user_id) GROUP BY 1;
3,057
Employees Project Allocation
Hard
<p>Table: <code>Project</code></p> <pre> +-------------+---------+ | Column Name | Type | +-------------+---------+ | project_id | int | | employee_id | int | | workload | int | +-------------+---------+ employee_id is the primary key (column with unique values) of this table. employee_id is a foreign key (reference column) to <code>Employee</code> table. Each row of this table indicates that the employee with employee_id is working on the project with project_id and the workload of the project. </pre> <p>Table: <code>Employees</code></p> <pre> +------------------+---------+ | Column Name | Type | +------------------+---------+ | employee_id | int | | name | varchar | | team | varchar | +------------------+---------+ employee_id is the primary key (column with unique values) of this table. Each row of this table contains information about one employee. </pre> <p>Write a solution to find the <strong>employees</strong> who are allocated to projects with a <strong>workload that exceeds the average</strong> workload of all employees for <strong>their respective teams</strong></p> <p>Return t<em>he result table ordered by</em> <code>employee_id</code>, <code>project_id</code> <em>in <strong>ascending</strong> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong>Example 1:</strong></p> <pre> <strong>Input:</strong> Project table: +-------------+-------------+----------+ | project_id | employee_id | workload | +-------------+-------------+----------+ | 1 | 1 | 45 | | 1 | 2 | 90 | | 2 | 3 | 12 | | 2 | 4 | 68 | +-------------+-------------+----------+ Employees table: +-------------+--------+------+ | employee_id | name | team | +-------------+--------+------+ | 1 | Khaled | A | | 2 | Ali | B | | 3 | John | B | | 4 | Doe | A | +-------------+--------+------+ <strong>Output:</strong> +-------------+------------+---------------+------------------+ | employee_id | project_id | employee_name | project_workload | +-------------+------------+---------------+------------------+ | 2 | 1 | Ali | 90 | | 4 | 2 | Doe | 68 | +-------------+------------+---------------+------------------+ <strong>Explanation:</strong> - Employee with ID 1 has a project workload of 45 and belongs to Team A, where the average workload is 56.50. Since his project workload does not exceed the team&#39;s average workload, he will be excluded. - Employee with ID 2 has a project workload of 90 and belongs to Team B, where the average workload is 51.00. Since his project workload does exceed the team&#39;s average workload, he will be included. - Employee with ID 3 has a project workload of 12 and belongs to Team B, where the average workload is 51.00. Since his project workload does not exceed the team&#39;s average workload, he will be excluded. - Employee with ID 4 has a project workload of 68 and belongs to Team A, where the average workload is 56.50. Since his project workload does exceed the team&#39;s average workload, he will be included. Result table orderd by employee_id, project_id in ascending order. </pre>
Database
Python
import pandas as pd def employees_with_above_avg_workload( project: pd.DataFrame, employees: pd.DataFrame ) -> pd.DataFrame: merged_df = pd.merge(project, employees, on="employee_id") avg_workload_per_team = merged_df.groupby("team")["workload"].mean().reset_index() merged_df = pd.merge( merged_df, avg_workload_per_team, on="team", suffixes=("", "_avg") ) ans = merged_df[merged_df["workload"] > merged_df["workload_avg"]] ans = ans[["employee_id", "project_id", "name", "workload"]] ans = ans.rename(columns={"name": "employee_name", "workload": "project_workload"}) return ans.sort_values(by=["employee_id", "project_id"])
3,057
Employees Project Allocation
Hard
<p>Table: <code>Project</code></p> <pre> +-------------+---------+ | Column Name | Type | +-------------+---------+ | project_id | int | | employee_id | int | | workload | int | +-------------+---------+ employee_id is the primary key (column with unique values) of this table. employee_id is a foreign key (reference column) to <code>Employee</code> table. Each row of this table indicates that the employee with employee_id is working on the project with project_id and the workload of the project. </pre> <p>Table: <code>Employees</code></p> <pre> +------------------+---------+ | Column Name | Type | +------------------+---------+ | employee_id | int | | name | varchar | | team | varchar | +------------------+---------+ employee_id is the primary key (column with unique values) of this table. Each row of this table contains information about one employee. </pre> <p>Write a solution to find the <strong>employees</strong> who are allocated to projects with a <strong>workload that exceeds the average</strong> workload of all employees for <strong>their respective teams</strong></p> <p>Return t<em>he result table ordered by</em> <code>employee_id</code>, <code>project_id</code> <em>in <strong>ascending</strong> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong>Example 1:</strong></p> <pre> <strong>Input:</strong> Project table: +-------------+-------------+----------+ | project_id | employee_id | workload | +-------------+-------------+----------+ | 1 | 1 | 45 | | 1 | 2 | 90 | | 2 | 3 | 12 | | 2 | 4 | 68 | +-------------+-------------+----------+ Employees table: +-------------+--------+------+ | employee_id | name | team | +-------------+--------+------+ | 1 | Khaled | A | | 2 | Ali | B | | 3 | John | B | | 4 | Doe | A | +-------------+--------+------+ <strong>Output:</strong> +-------------+------------+---------------+------------------+ | employee_id | project_id | employee_name | project_workload | +-------------+------------+---------------+------------------+ | 2 | 1 | Ali | 90 | | 4 | 2 | Doe | 68 | +-------------+------------+---------------+------------------+ <strong>Explanation:</strong> - Employee with ID 1 has a project workload of 45 and belongs to Team A, where the average workload is 56.50. Since his project workload does not exceed the team&#39;s average workload, he will be excluded. - Employee with ID 2 has a project workload of 90 and belongs to Team B, where the average workload is 51.00. Since his project workload does exceed the team&#39;s average workload, he will be included. - Employee with ID 3 has a project workload of 12 and belongs to Team B, where the average workload is 51.00. Since his project workload does not exceed the team&#39;s average workload, he will be excluded. - Employee with ID 4 has a project workload of 68 and belongs to Team A, where the average workload is 56.50. Since his project workload does exceed the team&#39;s average workload, he will be included. Result table orderd by employee_id, project_id in ascending order. </pre>
Database
SQL
# Write your MySQL query statement below WITH T AS ( SELECT team, AVG(workload) AS avg_workload FROM Project JOIN Employees USING (employee_id) GROUP BY 1 ) SELECT employee_id, project_id, name AS employee_name, workload AS project_workload FROM Project JOIN Employees USING (employee_id) JOIN T USING (team) WHERE workload > avg_workload ORDER BY 1, 2;
3,058
Friends With No Mutual Friends
Medium
<p>Table: <code>Friends</code></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | user_id1 | int | | user_id2 | int | +-------------+------+ (user_id1, user_id2) is the primary key (combination of columns with unique values) for this table. Each row contains user id1, user id2, both of whom are friends with each other. </pre> <p>Write a solution to find <strong>all</strong> <strong>pairs</strong> of users who are friends with each other and have <strong>no mutual</strong> friends.</p> <p>Return <em>the result table ordered by </em><code>user_id1,</code> <code>user_id2</code><em> in <strong>ascending</strong></em><em><strong> </strong>order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Friends table: +----------+----------+ | user_id1 | user_id2 | +----------+----------+ | 1 | 2 | | 2 | 3 | | 2 | 4 | | 1 | 5 | | 6 | 7 | | 3 | 4 | | 2 | 5 | | 8 | 9 | +----------+----------+ <strong>Output:</strong> +----------+----------+ | user_id1 | user_id2 | +----------+----------+ | 6 | 7 | | 8 | 9 | +----------+----------+ <strong>Explanation:</strong> - Users 1 and 2 are friends with each other, but they share a mutual friend with user ID 5, so this pair is not included. - Users 2 and 3 are friends, they both share a mutual friend with user ID 4, resulting in exclusion, similarly for users 2 and 4 who share a mutual friend with user ID 3, hence not included. - Users 1 and 5 are friends with each other, but they share a mutual friend with user ID 2, so this pair is not included. - Users 6 and 7, as well as users 8 and 9, are friends with each other, and they don&#39;t have any mutual friends, hence included. - Users 3 and 4 are friends with each other, but their mutual connection with user ID 2 means they are not included, similarly for users 2 and 5 are friends but are excluded due to their mutual connection with user ID 1. Output table is ordered by user_id1 in ascending order.</pre>
Database
Python
import pandas as pd def friends_with_no_mutual_friends(friends: pd.DataFrame) -> pd.DataFrame: cp = friends.copy() t = cp[["user_id1", "user_id2"]].copy() t = pd.concat( [ t, cp[["user_id2", "user_id1"]].rename( columns={"user_id2": "user_id1", "user_id1": "user_id2"} ), ] ) merged = t.merge(t, left_on="user_id2", right_on="user_id2") ans = cp[ ~cp.apply( lambda x: (x["user_id1"], x["user_id2"]) in zip(merged["user_id1_x"], merged["user_id1_y"]), axis=1, ) ] return ans.sort_values(by=["user_id1", "user_id2"])
3,058
Friends With No Mutual Friends
Medium
<p>Table: <code>Friends</code></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | user_id1 | int | | user_id2 | int | +-------------+------+ (user_id1, user_id2) is the primary key (combination of columns with unique values) for this table. Each row contains user id1, user id2, both of whom are friends with each other. </pre> <p>Write a solution to find <strong>all</strong> <strong>pairs</strong> of users who are friends with each other and have <strong>no mutual</strong> friends.</p> <p>Return <em>the result table ordered by </em><code>user_id1,</code> <code>user_id2</code><em> in <strong>ascending</strong></em><em><strong> </strong>order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Friends table: +----------+----------+ | user_id1 | user_id2 | +----------+----------+ | 1 | 2 | | 2 | 3 | | 2 | 4 | | 1 | 5 | | 6 | 7 | | 3 | 4 | | 2 | 5 | | 8 | 9 | +----------+----------+ <strong>Output:</strong> +----------+----------+ | user_id1 | user_id2 | +----------+----------+ | 6 | 7 | | 8 | 9 | +----------+----------+ <strong>Explanation:</strong> - Users 1 and 2 are friends with each other, but they share a mutual friend with user ID 5, so this pair is not included. - Users 2 and 3 are friends, they both share a mutual friend with user ID 4, resulting in exclusion, similarly for users 2 and 4 who share a mutual friend with user ID 3, hence not included. - Users 1 and 5 are friends with each other, but they share a mutual friend with user ID 2, so this pair is not included. - Users 6 and 7, as well as users 8 and 9, are friends with each other, and they don&#39;t have any mutual friends, hence included. - Users 3 and 4 are friends with each other, but their mutual connection with user ID 2 means they are not included, similarly for users 2 and 5 are friends but are excluded due to their mutual connection with user ID 1. Output table is ordered by user_id1 in ascending order.</pre>
Database
SQL
# Write your MySQL query statement below WITH T AS ( SELECT user_id1, user_id2 FROM Friends UNION ALL SELECT user_id2, user_id1 FROM Friends ) SELECT user_id1, user_id2 FROM Friends WHERE (user_id1, user_id2) NOT IN ( SELECT t1.user_id1, t2.user_id1 FROM T AS t1 JOIN T AS t2 ON t1.user_id2 = t2.user_id2 ) ORDER BY 1, 2;
3,059
Find All Unique Email Domains
Easy
<p>Table: <code>Emails</code></p> <pre> +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | email | varchar | +-------------+---------+ id is the primary key (column with unique values) for this table. Each row of this table contains an email. The emails will not contain uppercase letters. </pre> <p>Write a solution to find all <strong>unique email domains</strong> and count the number of <strong>individuals</strong> associated with each domain. <strong>Consider only</strong> those domains that <strong>end</strong> with <strong>.com</strong>.</p> <p>Return <em>the result table orderd by email domains in </em><strong>ascending</strong><em> order</em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Emails table: +-----+-----------------------+ | id | email | +-----+-----------------------+ | 336 | hwkiy@test.edu | | 489 | adcmaf@outlook.com | | 449 | vrzmwyum@yahoo.com | | 95 | tof@test.edu | | 320 | jxhbagkpm@example.org | | 411 | zxcf@outlook.com | +----+------------------------+ <strong>Output:</strong> +--------------+-------+ | email_domain | count | +--------------+-------+ | outlook.com | 2 | | yahoo.com | 1 | +--------------+-------+ <strong>Explanation:</strong> - The valid domains ending with &quot;.com&quot; are only &quot;outlook.com&quot; and &quot;yahoo.com&quot;, with respective counts of 2 and 1. Output table is ordered by email_domains in ascending order. </pre>
Database
Python
import pandas as pd def find_unique_email_domains(emails: pd.DataFrame) -> pd.DataFrame: emails["email_domain"] = emails["email"].str.split("@").str[-1] emails = emails[emails["email"].str.contains(".com")] return ( emails.groupby("email_domain") .size() .reset_index(name="count") .sort_values(by="email_domain") )
3,059
Find All Unique Email Domains
Easy
<p>Table: <code>Emails</code></p> <pre> +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | email | varchar | +-------------+---------+ id is the primary key (column with unique values) for this table. Each row of this table contains an email. The emails will not contain uppercase letters. </pre> <p>Write a solution to find all <strong>unique email domains</strong> and count the number of <strong>individuals</strong> associated with each domain. <strong>Consider only</strong> those domains that <strong>end</strong> with <strong>.com</strong>.</p> <p>Return <em>the result table orderd by email domains in </em><strong>ascending</strong><em> order</em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Emails table: +-----+-----------------------+ | id | email | +-----+-----------------------+ | 336 | hwkiy@test.edu | | 489 | adcmaf@outlook.com | | 449 | vrzmwyum@yahoo.com | | 95 | tof@test.edu | | 320 | jxhbagkpm@example.org | | 411 | zxcf@outlook.com | +----+------------------------+ <strong>Output:</strong> +--------------+-------+ | email_domain | count | +--------------+-------+ | outlook.com | 2 | | yahoo.com | 1 | +--------------+-------+ <strong>Explanation:</strong> - The valid domains ending with &quot;.com&quot; are only &quot;outlook.com&quot; and &quot;yahoo.com&quot;, with respective counts of 2 and 1. Output table is ordered by email_domains in ascending order. </pre>
Database
SQL
# Write your MySQL query statement below SELECT SUBSTRING_INDEX(email, '@', -1) AS email_domain, COUNT(1) AS count FROM Emails WHERE email LIKE '%.com' GROUP BY 1 ORDER BY 1;
3,060
User Activities within Time Bounds
Hard
<p>Table: <code>Sessions</code></p> <pre> +---------------+----------+ | Column Name | Type | +---------------+----------+ | user_id | int | | session_start | datetime | | session_end | datetime | | session_id | int | | session_type | enum | +---------------+----------+ session_id is column of unique values for this table. session_type is an ENUM (category) type of (Viewer, Streamer). This table contains user id, session start, session end, session id and session type. </pre> <p>Write a solution to find the the <strong>users</strong> who have had <strong>at least two</strong><strong>&nbsp;session</strong> of the <strong>same</strong> type (either &#39;<strong>Viewer</strong>&#39; or &#39;<strong>Streamer</strong>&#39;) with a <strong>maximum</strong> gap of <code>12</code> hours <strong>between</strong> sessions.</p> <p>Return <em>the result table ordered by </em><code>user_id</code><em> in <b>ascending</b> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <pre> <strong>Input:</strong> Sessions table: +---------+---------------------+---------------------+------------+--------------+ | user_id | session_start | session_end | session_id | session_type | +---------+---------------------+---------------------+------------+--------------+ | 101 | 2023-11-01 08:00:00 | 2023-11-01 09:00:00 | 1 | Viewer | | 101 | 2023-11-01 10:00:00 | 2023-11-01 11:00:00 | 2 | Streamer | | 102 | 2023-11-01 13:00:00 | 2023-11-01 14:00:00 | 3 | Viewer | | 102 | 2023-11-01 15:00:00 | 2023-11-01 16:00:00 | 4 | Viewer | | 101 | 2023-11-02 09:00:00 | 2023-11-02 10:00:00 | 5 | Viewer | | 102 | 2023-11-02 12:00:00 | 2023-11-02 13:00:00 | 6 | Streamer | | 101 | 2023-11-02 13:00:00 | 2023-11-02 14:00:00 | 7 | Streamer | | 102 | 2023-11-02 16:00:00 | 2023-11-02 17:00:00 | 8 | Viewer | | 103 | 2023-11-01 08:00:00 | 2023-11-01 09:00:00 | 9 | Viewer | | 103 | 2023-11-02 20:00:00 | 2023-11-02 23:00:00 | 10 | Viewer | | 103 | 2023-11-03 09:00:00 | 2023-11-03 10:00:00 | 11 | Viewer | +---------+---------------------+---------------------+------------+--------------+ <strong>Output:</strong> +---------+ | user_id | +---------+ | 102 | | 103 | +---------+ <strong>Explanation:</strong> - User ID 101 will not be included in the final output as they do not have any two sessions of the same session type. - User ID 102 will be included in the final output as they had two viewer sessions with session IDs 3 and 4, respectively, and the time gap between them was less than 12 hours. - User ID 103 participated in two viewer sessions with a gap of less than 12 hours between them, identified by session IDs 10 and 11. Therefore, user 103 will be included in the final output. Output table is ordered by user_id in increasing order. </pre>
Database
Python
import pandas as pd def user_activities(sessions: pd.DataFrame) -> pd.DataFrame: sessions = sessions.sort_values(by=["user_id", "session_start"]) sessions["prev_session_end"] = sessions.groupby(["user_id", "session_type"])[ "session_end" ].shift(1) sessions_filtered = sessions[ sessions["session_start"] - sessions["prev_session_end"] <= pd.Timedelta(hours=12) ] return pd.DataFrame({"user_id": sessions_filtered["user_id"].unique()})
3,060
User Activities within Time Bounds
Hard
<p>Table: <code>Sessions</code></p> <pre> +---------------+----------+ | Column Name | Type | +---------------+----------+ | user_id | int | | session_start | datetime | | session_end | datetime | | session_id | int | | session_type | enum | +---------------+----------+ session_id is column of unique values for this table. session_type is an ENUM (category) type of (Viewer, Streamer). This table contains user id, session start, session end, session id and session type. </pre> <p>Write a solution to find the the <strong>users</strong> who have had <strong>at least two</strong><strong>&nbsp;session</strong> of the <strong>same</strong> type (either &#39;<strong>Viewer</strong>&#39; or &#39;<strong>Streamer</strong>&#39;) with a <strong>maximum</strong> gap of <code>12</code> hours <strong>between</strong> sessions.</p> <p>Return <em>the result table ordered by </em><code>user_id</code><em> in <b>ascending</b> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <pre> <strong>Input:</strong> Sessions table: +---------+---------------------+---------------------+------------+--------------+ | user_id | session_start | session_end | session_id | session_type | +---------+---------------------+---------------------+------------+--------------+ | 101 | 2023-11-01 08:00:00 | 2023-11-01 09:00:00 | 1 | Viewer | | 101 | 2023-11-01 10:00:00 | 2023-11-01 11:00:00 | 2 | Streamer | | 102 | 2023-11-01 13:00:00 | 2023-11-01 14:00:00 | 3 | Viewer | | 102 | 2023-11-01 15:00:00 | 2023-11-01 16:00:00 | 4 | Viewer | | 101 | 2023-11-02 09:00:00 | 2023-11-02 10:00:00 | 5 | Viewer | | 102 | 2023-11-02 12:00:00 | 2023-11-02 13:00:00 | 6 | Streamer | | 101 | 2023-11-02 13:00:00 | 2023-11-02 14:00:00 | 7 | Streamer | | 102 | 2023-11-02 16:00:00 | 2023-11-02 17:00:00 | 8 | Viewer | | 103 | 2023-11-01 08:00:00 | 2023-11-01 09:00:00 | 9 | Viewer | | 103 | 2023-11-02 20:00:00 | 2023-11-02 23:00:00 | 10 | Viewer | | 103 | 2023-11-03 09:00:00 | 2023-11-03 10:00:00 | 11 | Viewer | +---------+---------------------+---------------------+------------+--------------+ <strong>Output:</strong> +---------+ | user_id | +---------+ | 102 | | 103 | +---------+ <strong>Explanation:</strong> - User ID 101 will not be included in the final output as they do not have any two sessions of the same session type. - User ID 102 will be included in the final output as they had two viewer sessions with session IDs 3 and 4, respectively, and the time gap between them was less than 12 hours. - User ID 103 participated in two viewer sessions with a gap of less than 12 hours between them, identified by session IDs 10 and 11. Therefore, user 103 will be included in the final output. Output table is ordered by user_id in increasing order. </pre>
Database
SQL
# Write your MySQL query statement below WITH T AS ( SELECT user_id, session_start, LAG(session_end) OVER ( PARTITION BY user_id, session_type ORDER BY session_end ) AS prev_session_end FROM Sessions ) SELECT DISTINCT user_id FROM T WHERE TIMESTAMPDIFF(HOUR, prev_session_end, session_start) <= 12;
3,061
Calculate Trapping Rain Water
Hard
<p>Table: <font face="monospace">Heights</font></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | id | int | | height | int | +-------------+------+ id is the primary key (column with unique values) for this table, and it is guaranteed to be in sequential order. Each row of this table contains an id and height. </pre> <p>Write a solution to calculate the amount of rainwater can be <strong>trapped between the bars</strong> in the landscape, considering that each bar has a <strong>width</strong> of <code>1</code> unit.</p> <p>Return <em>the result table in </em><strong>any</strong><em> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Heights table: +-----+--------+ | id | height | +-----+--------+ | 1 | 0 | | 2 | 1 | | 3 | 0 | | 4 | 2 | | 5 | 1 | | 6 | 0 | | 7 | 1 | | 8 | 3 | | 9 | 2 | | 10 | 1 | | 11 | 2 | | 12 | 1 | +-----+--------+ <strong>Output:</strong> +---------------------+ | total_trapped_water | +---------------------+ | 6 | +---------------------+ <strong>Explanation:</strong> <img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3061.Calculate%20Trapping%20Rain%20Water/images/trapping_rain_water.png" style="width:500px; height:200px;" /> The elevation map depicted above (in the black section) is graphically represented with the x-axis denoting the id and the y-axis representing the heights [0,1,0,2,1,0,1,3,2,1,2,1]. In this scenario, 6 units of rainwater are trapped within the blue section. </pre>
Database
Python
import pandas as pd def calculate_trapped_rain_water(heights: pd.DataFrame) -> pd.DataFrame: heights["l"] = heights["height"].cummax() heights["r"] = heights["height"][::-1].cummax()[::-1] heights["trapped_water"] = heights[["l", "r"]].min(axis=1) - heights["height"] return pd.DataFrame({"total_trapped_water": [heights["trapped_water"].sum()]})
3,061
Calculate Trapping Rain Water
Hard
<p>Table: <font face="monospace">Heights</font></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | id | int | | height | int | +-------------+------+ id is the primary key (column with unique values) for this table, and it is guaranteed to be in sequential order. Each row of this table contains an id and height. </pre> <p>Write a solution to calculate the amount of rainwater can be <strong>trapped between the bars</strong> in the landscape, considering that each bar has a <strong>width</strong> of <code>1</code> unit.</p> <p>Return <em>the result table in </em><strong>any</strong><em> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> Heights table: +-----+--------+ | id | height | +-----+--------+ | 1 | 0 | | 2 | 1 | | 3 | 0 | | 4 | 2 | | 5 | 1 | | 6 | 0 | | 7 | 1 | | 8 | 3 | | 9 | 2 | | 10 | 1 | | 11 | 2 | | 12 | 1 | +-----+--------+ <strong>Output:</strong> +---------------------+ | total_trapped_water | +---------------------+ | 6 | +---------------------+ <strong>Explanation:</strong> <img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3061.Calculate%20Trapping%20Rain%20Water/images/trapping_rain_water.png" style="width:500px; height:200px;" /> The elevation map depicted above (in the black section) is graphically represented with the x-axis denoting the id and the y-axis representing the heights [0,1,0,2,1,0,1,3,2,1,2,1]. In this scenario, 6 units of rainwater are trapped within the blue section. </pre>
Database
SQL
# Write your MySQL query statement below WITH T AS ( SELECT *, MAX(height) OVER (ORDER BY id) AS l, MAX(height) OVER (ORDER BY id DESC) AS r FROM Heights ) SELECT SUM(LEAST(l, r) - height) AS total_trapped_water FROM T;
3,062
Winner of the Linked List Game
Easy
<p>You are given the <code>head</code> of a linked list of <strong>even</strong> length containing integers.</p> <p>Each <strong>odd-indexed</strong> node contains an odd integer and each <strong>even-indexed</strong> node contains an even integer.</p> <p>We call each even-indexed node and its next node a <strong>pair</strong>, e.g., the nodes with indices <code>0</code> and <code>1</code> are a pair, the nodes with indices <code>2</code> and <code>3</code> are a pair, and so on.</p> <p>For every <strong>pair</strong>, we compare the values of the nodes in the pair:</p> <ul> <li>If the odd-indexed node is higher, the <code>&quot;Odd&quot;</code> team gets a point.</li> <li>If the even-indexed node is higher, the <code>&quot;Even&quot;</code> team gets a point.</li> </ul> <p>Return <em>the name of the team with the <strong>higher</strong> points, if the points are equal, return</em> <code>&quot;Tie&quot;</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Even&quot; </span></p> <p><strong>Explanation: </strong> There is only one pair in this linked list and that is <code>(2,1)</code>. Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Hence, the answer would be <code>&quot;Even&quot;</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,5,4,7,20,5] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Odd&quot; </span></p> <p><strong>Explanation: </strong> There are <code>3</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(2,5)</code> -&gt; Since <code>2 &lt; 5</code>, The Odd team gets the point.</p> <p><code>(4,7)</code> -&gt; Since <code>4 &lt; 7</code>, The Odd team gets the point.</p> <p><code>(20,5)</code> -&gt; Since <code>20 &gt; 5</code>, The Even team gets the point.</p> <p>The Odd team earned <code>2</code> points while the Even team got <code>1</code> point and the Odd team has the higher points.</p> <p>Hence, the answer would be <code>&quot;Odd&quot;</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [4,5,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Tie&quot; </span></p> <p><strong>Explanation: </strong> There are <code>2</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(4,5)</code> -&gt; Since <code>4 &lt; 5</code>, the Odd team gets the point.</p> <p><code>(2,1)</code> -&gt; Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Both teams earned <code>1</code> point.</p> <p>Hence, the answer would be <code>&quot;Tie&quot;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[2, 100]</code>.</li> <li>The number of nodes in the list is even.</li> <li><code>1 &lt;= Node.val &lt;= 100</code></li> <li>The value of each odd-indexed node is odd.</li> <li>The value of each even-indexed node is even.</li> </ul>
Linked List
C++
/** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode() : val(0), next(nullptr) {} * ListNode(int x) : val(x), next(nullptr) {} * ListNode(int x, ListNode *next) : val(x), next(next) {} * }; */ class Solution { public: string gameResult(ListNode* head) { int odd = 0, even = 0; for (; head != nullptr; head = head->next->next) { int a = head->val; int b = head->next->val; odd += a < b; even += a > b; } if (odd > even) { return "Odd"; } if (odd < even) { return "Even"; } return "Tie"; } };
3,062
Winner of the Linked List Game
Easy
<p>You are given the <code>head</code> of a linked list of <strong>even</strong> length containing integers.</p> <p>Each <strong>odd-indexed</strong> node contains an odd integer and each <strong>even-indexed</strong> node contains an even integer.</p> <p>We call each even-indexed node and its next node a <strong>pair</strong>, e.g., the nodes with indices <code>0</code> and <code>1</code> are a pair, the nodes with indices <code>2</code> and <code>3</code> are a pair, and so on.</p> <p>For every <strong>pair</strong>, we compare the values of the nodes in the pair:</p> <ul> <li>If the odd-indexed node is higher, the <code>&quot;Odd&quot;</code> team gets a point.</li> <li>If the even-indexed node is higher, the <code>&quot;Even&quot;</code> team gets a point.</li> </ul> <p>Return <em>the name of the team with the <strong>higher</strong> points, if the points are equal, return</em> <code>&quot;Tie&quot;</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Even&quot; </span></p> <p><strong>Explanation: </strong> There is only one pair in this linked list and that is <code>(2,1)</code>. Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Hence, the answer would be <code>&quot;Even&quot;</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,5,4,7,20,5] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Odd&quot; </span></p> <p><strong>Explanation: </strong> There are <code>3</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(2,5)</code> -&gt; Since <code>2 &lt; 5</code>, The Odd team gets the point.</p> <p><code>(4,7)</code> -&gt; Since <code>4 &lt; 7</code>, The Odd team gets the point.</p> <p><code>(20,5)</code> -&gt; Since <code>20 &gt; 5</code>, The Even team gets the point.</p> <p>The Odd team earned <code>2</code> points while the Even team got <code>1</code> point and the Odd team has the higher points.</p> <p>Hence, the answer would be <code>&quot;Odd&quot;</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [4,5,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Tie&quot; </span></p> <p><strong>Explanation: </strong> There are <code>2</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(4,5)</code> -&gt; Since <code>4 &lt; 5</code>, the Odd team gets the point.</p> <p><code>(2,1)</code> -&gt; Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Both teams earned <code>1</code> point.</p> <p>Hence, the answer would be <code>&quot;Tie&quot;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[2, 100]</code>.</li> <li>The number of nodes in the list is even.</li> <li><code>1 &lt;= Node.val &lt;= 100</code></li> <li>The value of each odd-indexed node is odd.</li> <li>The value of each even-indexed node is even.</li> </ul>
Linked List
Go
/** * Definition for singly-linked list. * type ListNode struct { * Val int * Next *ListNode * } */ func gameResult(head *ListNode) string { var odd, even int for ; head != nil; head = head.Next.Next { a, b := head.Val, head.Next.Val if a < b { odd++ } if a > b { even++ } } if odd > even { return "Odd" } if odd < even { return "Even" } return "Tie" }
3,062
Winner of the Linked List Game
Easy
<p>You are given the <code>head</code> of a linked list of <strong>even</strong> length containing integers.</p> <p>Each <strong>odd-indexed</strong> node contains an odd integer and each <strong>even-indexed</strong> node contains an even integer.</p> <p>We call each even-indexed node and its next node a <strong>pair</strong>, e.g., the nodes with indices <code>0</code> and <code>1</code> are a pair, the nodes with indices <code>2</code> and <code>3</code> are a pair, and so on.</p> <p>For every <strong>pair</strong>, we compare the values of the nodes in the pair:</p> <ul> <li>If the odd-indexed node is higher, the <code>&quot;Odd&quot;</code> team gets a point.</li> <li>If the even-indexed node is higher, the <code>&quot;Even&quot;</code> team gets a point.</li> </ul> <p>Return <em>the name of the team with the <strong>higher</strong> points, if the points are equal, return</em> <code>&quot;Tie&quot;</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Even&quot; </span></p> <p><strong>Explanation: </strong> There is only one pair in this linked list and that is <code>(2,1)</code>. Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Hence, the answer would be <code>&quot;Even&quot;</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,5,4,7,20,5] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Odd&quot; </span></p> <p><strong>Explanation: </strong> There are <code>3</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(2,5)</code> -&gt; Since <code>2 &lt; 5</code>, The Odd team gets the point.</p> <p><code>(4,7)</code> -&gt; Since <code>4 &lt; 7</code>, The Odd team gets the point.</p> <p><code>(20,5)</code> -&gt; Since <code>20 &gt; 5</code>, The Even team gets the point.</p> <p>The Odd team earned <code>2</code> points while the Even team got <code>1</code> point and the Odd team has the higher points.</p> <p>Hence, the answer would be <code>&quot;Odd&quot;</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [4,5,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Tie&quot; </span></p> <p><strong>Explanation: </strong> There are <code>2</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(4,5)</code> -&gt; Since <code>4 &lt; 5</code>, the Odd team gets the point.</p> <p><code>(2,1)</code> -&gt; Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Both teams earned <code>1</code> point.</p> <p>Hence, the answer would be <code>&quot;Tie&quot;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[2, 100]</code>.</li> <li>The number of nodes in the list is even.</li> <li><code>1 &lt;= Node.val &lt;= 100</code></li> <li>The value of each odd-indexed node is odd.</li> <li>The value of each even-indexed node is even.</li> </ul>
Linked List
Java
/** * Definition for singly-linked list. * public class ListNode { * int val; * ListNode next; * ListNode() {} * ListNode(int val) { this.val = val; } * ListNode(int val, ListNode next) { this.val = val; this.next = next; } * } */ class Solution { public String gameResult(ListNode head) { int odd = 0, even = 0; for (; head != null; head = head.next.next) { int a = head.val; int b = head.next.val; odd += a < b ? 1 : 0; even += a > b ? 1 : 0; } if (odd > even) { return "Odd"; } if (odd < even) { return "Even"; } return "Tie"; } }
3,062
Winner of the Linked List Game
Easy
<p>You are given the <code>head</code> of a linked list of <strong>even</strong> length containing integers.</p> <p>Each <strong>odd-indexed</strong> node contains an odd integer and each <strong>even-indexed</strong> node contains an even integer.</p> <p>We call each even-indexed node and its next node a <strong>pair</strong>, e.g., the nodes with indices <code>0</code> and <code>1</code> are a pair, the nodes with indices <code>2</code> and <code>3</code> are a pair, and so on.</p> <p>For every <strong>pair</strong>, we compare the values of the nodes in the pair:</p> <ul> <li>If the odd-indexed node is higher, the <code>&quot;Odd&quot;</code> team gets a point.</li> <li>If the even-indexed node is higher, the <code>&quot;Even&quot;</code> team gets a point.</li> </ul> <p>Return <em>the name of the team with the <strong>higher</strong> points, if the points are equal, return</em> <code>&quot;Tie&quot;</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Even&quot; </span></p> <p><strong>Explanation: </strong> There is only one pair in this linked list and that is <code>(2,1)</code>. Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Hence, the answer would be <code>&quot;Even&quot;</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,5,4,7,20,5] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Odd&quot; </span></p> <p><strong>Explanation: </strong> There are <code>3</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(2,5)</code> -&gt; Since <code>2 &lt; 5</code>, The Odd team gets the point.</p> <p><code>(4,7)</code> -&gt; Since <code>4 &lt; 7</code>, The Odd team gets the point.</p> <p><code>(20,5)</code> -&gt; Since <code>20 &gt; 5</code>, The Even team gets the point.</p> <p>The Odd team earned <code>2</code> points while the Even team got <code>1</code> point and the Odd team has the higher points.</p> <p>Hence, the answer would be <code>&quot;Odd&quot;</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [4,5,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Tie&quot; </span></p> <p><strong>Explanation: </strong> There are <code>2</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(4,5)</code> -&gt; Since <code>4 &lt; 5</code>, the Odd team gets the point.</p> <p><code>(2,1)</code> -&gt; Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Both teams earned <code>1</code> point.</p> <p>Hence, the answer would be <code>&quot;Tie&quot;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[2, 100]</code>.</li> <li>The number of nodes in the list is even.</li> <li><code>1 &lt;= Node.val &lt;= 100</code></li> <li>The value of each odd-indexed node is odd.</li> <li>The value of each even-indexed node is even.</li> </ul>
Linked List
Python
# Definition for singly-linked list. # class ListNode: # def __init__(self, val=0, next=None): # self.val = val # self.next = next class Solution: def gameResult(self, head: Optional[ListNode]) -> str: odd = even = 0 while head: a = head.val b = head.next.val odd += a < b even += a > b head = head.next.next if odd > even: return "Odd" if odd < even: return "Even" return "Tie"
3,062
Winner of the Linked List Game
Easy
<p>You are given the <code>head</code> of a linked list of <strong>even</strong> length containing integers.</p> <p>Each <strong>odd-indexed</strong> node contains an odd integer and each <strong>even-indexed</strong> node contains an even integer.</p> <p>We call each even-indexed node and its next node a <strong>pair</strong>, e.g., the nodes with indices <code>0</code> and <code>1</code> are a pair, the nodes with indices <code>2</code> and <code>3</code> are a pair, and so on.</p> <p>For every <strong>pair</strong>, we compare the values of the nodes in the pair:</p> <ul> <li>If the odd-indexed node is higher, the <code>&quot;Odd&quot;</code> team gets a point.</li> <li>If the even-indexed node is higher, the <code>&quot;Even&quot;</code> team gets a point.</li> </ul> <p>Return <em>the name of the team with the <strong>higher</strong> points, if the points are equal, return</em> <code>&quot;Tie&quot;</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Even&quot; </span></p> <p><strong>Explanation: </strong> There is only one pair in this linked list and that is <code>(2,1)</code>. Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Hence, the answer would be <code>&quot;Even&quot;</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [2,5,4,7,20,5] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Odd&quot; </span></p> <p><strong>Explanation: </strong> There are <code>3</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(2,5)</code> -&gt; Since <code>2 &lt; 5</code>, The Odd team gets the point.</p> <p><code>(4,7)</code> -&gt; Since <code>4 &lt; 7</code>, The Odd team gets the point.</p> <p><code>(20,5)</code> -&gt; Since <code>20 &gt; 5</code>, The Even team gets the point.</p> <p>The Odd team earned <code>2</code> points while the Even team got <code>1</code> point and the Odd team has the higher points.</p> <p>Hence, the answer would be <code>&quot;Odd&quot;</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [4,5,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> &quot;Tie&quot; </span></p> <p><strong>Explanation: </strong> There are <code>2</code> pairs in this linked list. Let&#39;s investigate each pair individually:</p> <p><code>(4,5)</code> -&gt; Since <code>4 &lt; 5</code>, the Odd team gets the point.</p> <p><code>(2,1)</code> -&gt; Since <code>2 &gt; 1</code>, the Even team gets the point.</p> <p>Both teams earned <code>1</code> point.</p> <p>Hence, the answer would be <code>&quot;Tie&quot;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[2, 100]</code>.</li> <li>The number of nodes in the list is even.</li> <li><code>1 &lt;= Node.val &lt;= 100</code></li> <li>The value of each odd-indexed node is odd.</li> <li>The value of each even-indexed node is even.</li> </ul>
Linked List
TypeScript
/** * Definition for singly-linked list. * class ListNode { * val: number * next: ListNode | null * constructor(val?: number, next?: ListNode | null) { * this.val = (val===undefined ? 0 : val) * this.next = (next===undefined ? null : next) * } * } */ function gameResult(head: ListNode | null): string { let [odd, even] = [0, 0]; for (; head; head = head.next.next) { const [a, b] = [head.val, head.next.val]; odd += a < b ? 1 : 0; even += a > b ? 1 : 0; } if (odd > even) { return 'Odd'; } if (odd < even) { return 'Even'; } return 'Tie'; }
3,063
Linked List Frequency
Easy
<p>Given the <code>head</code> of a linked list containing <code>k</code> <strong>distinct</strong> elements, return <em>the head to a linked list of length </em><code>k</code><em> containing the <span data-keyword="frequency-linkedlist">frequency</span> of each <strong>distinct</strong> element in the given linked list in <strong>any order</strong>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,1,2,3] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [3,2,1] </span></p> <p><strong>Explanation: </strong> There are <code>3</code> distinct elements in the list. The frequency of <code>1</code> is <code>3</code>, the frequency of <code>2</code> is <code>2</code> and the frequency of <code>3</code> is <code>1</code>. Hence, we return <code>3 -&gt; 2 -&gt; 1</code>.</p> <p>Note that <code>1 -&gt; 2 -&gt; 3</code>, <code>1 -&gt; 3 -&gt; 2</code>, <code>2 -&gt; 1 -&gt; 3</code>, <code>2 -&gt; 3 -&gt; 1</code>, and <code>3 -&gt; 1 -&gt; 2</code> are also valid answers.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,2,2] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [2,3] </span></p> <p><strong>Explanation: </strong> There are <code>2</code> distinct elements in the list. The frequency of <code>1</code> is <code>2</code> and the frequency of <code>2</code> is <code>3</code>. Hence, we return <code>2 -&gt; 3</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [6,5,4,3,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [1,1,1,1,1,1] </span></p> <p><strong>Explanation: </strong> There are <code>6</code> distinct elements in the list. The frequency of each of them is <code>1</code>. Hence, we return <code>1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[1, 10<sup>5</sup>]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 10<sup>5</sup></code></li> </ul>
Hash Table; Linked List; Counting
C++
/** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode() : val(0), next(nullptr) {} * ListNode(int x) : val(x), next(nullptr) {} * ListNode(int x, ListNode *next) : val(x), next(next) {} * }; */ class Solution { public: ListNode* frequenciesOfElements(ListNode* head) { unordered_map<int, int> cnt; for (; head; head = head->next) { cnt[head->val]++; } ListNode* dummy = new ListNode(); for (auto& [_, val] : cnt) { dummy->next = new ListNode(val, dummy->next); } return dummy->next; } };
3,063
Linked List Frequency
Easy
<p>Given the <code>head</code> of a linked list containing <code>k</code> <strong>distinct</strong> elements, return <em>the head to a linked list of length </em><code>k</code><em> containing the <span data-keyword="frequency-linkedlist">frequency</span> of each <strong>distinct</strong> element in the given linked list in <strong>any order</strong>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,1,2,3] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [3,2,1] </span></p> <p><strong>Explanation: </strong> There are <code>3</code> distinct elements in the list. The frequency of <code>1</code> is <code>3</code>, the frequency of <code>2</code> is <code>2</code> and the frequency of <code>3</code> is <code>1</code>. Hence, we return <code>3 -&gt; 2 -&gt; 1</code>.</p> <p>Note that <code>1 -&gt; 2 -&gt; 3</code>, <code>1 -&gt; 3 -&gt; 2</code>, <code>2 -&gt; 1 -&gt; 3</code>, <code>2 -&gt; 3 -&gt; 1</code>, and <code>3 -&gt; 1 -&gt; 2</code> are also valid answers.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,2,2] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [2,3] </span></p> <p><strong>Explanation: </strong> There are <code>2</code> distinct elements in the list. The frequency of <code>1</code> is <code>2</code> and the frequency of <code>2</code> is <code>3</code>. Hence, we return <code>2 -&gt; 3</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [6,5,4,3,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [1,1,1,1,1,1] </span></p> <p><strong>Explanation: </strong> There are <code>6</code> distinct elements in the list. The frequency of each of them is <code>1</code>. Hence, we return <code>1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[1, 10<sup>5</sup>]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 10<sup>5</sup></code></li> </ul>
Hash Table; Linked List; Counting
Go
/** * Definition for singly-linked list. * type ListNode struct { * Val int * Next *ListNode * } */ func frequenciesOfElements(head *ListNode) *ListNode { cnt := map[int]int{} for ; head != nil; head = head.Next { cnt[head.Val]++ } dummy := &ListNode{} for _, val := range cnt { dummy.Next = &ListNode{val, dummy.Next} } return dummy.Next }
3,063
Linked List Frequency
Easy
<p>Given the <code>head</code> of a linked list containing <code>k</code> <strong>distinct</strong> elements, return <em>the head to a linked list of length </em><code>k</code><em> containing the <span data-keyword="frequency-linkedlist">frequency</span> of each <strong>distinct</strong> element in the given linked list in <strong>any order</strong>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,1,2,3] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [3,2,1] </span></p> <p><strong>Explanation: </strong> There are <code>3</code> distinct elements in the list. The frequency of <code>1</code> is <code>3</code>, the frequency of <code>2</code> is <code>2</code> and the frequency of <code>3</code> is <code>1</code>. Hence, we return <code>3 -&gt; 2 -&gt; 1</code>.</p> <p>Note that <code>1 -&gt; 2 -&gt; 3</code>, <code>1 -&gt; 3 -&gt; 2</code>, <code>2 -&gt; 1 -&gt; 3</code>, <code>2 -&gt; 3 -&gt; 1</code>, and <code>3 -&gt; 1 -&gt; 2</code> are also valid answers.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,2,2] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [2,3] </span></p> <p><strong>Explanation: </strong> There are <code>2</code> distinct elements in the list. The frequency of <code>1</code> is <code>2</code> and the frequency of <code>2</code> is <code>3</code>. Hence, we return <code>2 -&gt; 3</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [6,5,4,3,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [1,1,1,1,1,1] </span></p> <p><strong>Explanation: </strong> There are <code>6</code> distinct elements in the list. The frequency of each of them is <code>1</code>. Hence, we return <code>1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[1, 10<sup>5</sup>]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 10<sup>5</sup></code></li> </ul>
Hash Table; Linked List; Counting
Java
/** * Definition for singly-linked list. * public class ListNode { * int val; * ListNode next; * ListNode() {} * ListNode(int val) { this.val = val; } * ListNode(int val, ListNode next) { this.val = val; this.next = next; } * } */ class Solution { public ListNode frequenciesOfElements(ListNode head) { Map<Integer, Integer> cnt = new HashMap<>(); for (; head != null; head = head.next) { cnt.merge(head.val, 1, Integer::sum); } ListNode dummy = new ListNode(); for (int val : cnt.values()) { dummy.next = new ListNode(val, dummy.next); } return dummy.next; } }
3,063
Linked List Frequency
Easy
<p>Given the <code>head</code> of a linked list containing <code>k</code> <strong>distinct</strong> elements, return <em>the head to a linked list of length </em><code>k</code><em> containing the <span data-keyword="frequency-linkedlist">frequency</span> of each <strong>distinct</strong> element in the given linked list in <strong>any order</strong>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,1,2,3] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [3,2,1] </span></p> <p><strong>Explanation: </strong> There are <code>3</code> distinct elements in the list. The frequency of <code>1</code> is <code>3</code>, the frequency of <code>2</code> is <code>2</code> and the frequency of <code>3</code> is <code>1</code>. Hence, we return <code>3 -&gt; 2 -&gt; 1</code>.</p> <p>Note that <code>1 -&gt; 2 -&gt; 3</code>, <code>1 -&gt; 3 -&gt; 2</code>, <code>2 -&gt; 1 -&gt; 3</code>, <code>2 -&gt; 3 -&gt; 1</code>, and <code>3 -&gt; 1 -&gt; 2</code> are also valid answers.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,2,2] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [2,3] </span></p> <p><strong>Explanation: </strong> There are <code>2</code> distinct elements in the list. The frequency of <code>1</code> is <code>2</code> and the frequency of <code>2</code> is <code>3</code>. Hence, we return <code>2 -&gt; 3</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [6,5,4,3,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [1,1,1,1,1,1] </span></p> <p><strong>Explanation: </strong> There are <code>6</code> distinct elements in the list. The frequency of each of them is <code>1</code>. Hence, we return <code>1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[1, 10<sup>5</sup>]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 10<sup>5</sup></code></li> </ul>
Hash Table; Linked List; Counting
Python
# Definition for singly-linked list. # class ListNode: # def __init__(self, val=0, next=None): # self.val = val # self.next = next class Solution: def frequenciesOfElements(self, head: Optional[ListNode]) -> Optional[ListNode]: cnt = Counter() while head: cnt[head.val] += 1 head = head.next dummy = ListNode() for val in cnt.values(): dummy.next = ListNode(val, dummy.next) return dummy.next
3,063
Linked List Frequency
Easy
<p>Given the <code>head</code> of a linked list containing <code>k</code> <strong>distinct</strong> elements, return <em>the head to a linked list of length </em><code>k</code><em> containing the <span data-keyword="frequency-linkedlist">frequency</span> of each <strong>distinct</strong> element in the given linked list in <strong>any order</strong>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,1,2,3] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [3,2,1] </span></p> <p><strong>Explanation: </strong> There are <code>3</code> distinct elements in the list. The frequency of <code>1</code> is <code>3</code>, the frequency of <code>2</code> is <code>2</code> and the frequency of <code>3</code> is <code>1</code>. Hence, we return <code>3 -&gt; 2 -&gt; 1</code>.</p> <p>Note that <code>1 -&gt; 2 -&gt; 3</code>, <code>1 -&gt; 3 -&gt; 2</code>, <code>2 -&gt; 1 -&gt; 3</code>, <code>2 -&gt; 3 -&gt; 1</code>, and <code>3 -&gt; 1 -&gt; 2</code> are also valid answers.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [1,1,2,2,2] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [2,3] </span></p> <p><strong>Explanation: </strong> There are <code>2</code> distinct elements in the list. The frequency of <code>1</code> is <code>2</code> and the frequency of <code>2</code> is <code>3</code>. Hence, we return <code>2 -&gt; 3</code>.</p> </div> <p><strong class="example">Example 3: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> head = [6,5,4,3,2,1] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> [1,1,1,1,1,1] </span></p> <p><strong>Explanation: </strong> There are <code>6</code> distinct elements in the list. The frequency of each of them is <code>1</code>. Hence, we return <code>1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1 -&gt; 1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the list is in the range <code>[1, 10<sup>5</sup>]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 10<sup>5</sup></code></li> </ul>
Hash Table; Linked List; Counting
TypeScript
/** * Definition for singly-linked list. * class ListNode { * val: number * next: ListNode | null * constructor(val?: number, next?: ListNode | null) { * this.val = (val===undefined ? 0 : val) * this.next = (next===undefined ? null : next) * } * } */ function frequenciesOfElements(head: ListNode | null): ListNode | null { const cnt: Map<number, number> = new Map(); for (; head; head = head.next) { cnt.set(head.val, (cnt.get(head.val) || 0) + 1); } const dummy = new ListNode(); for (const val of cnt.values()) { dummy.next = new ListNode(val, dummy.next); } return dummy.next; }
3,064
Guess the Number Using Bitwise Questions I
Medium
<p>There is a number <code>n</code> that you have to find.</p> <p>There is also a pre-defined API <code>int commonSetBits(int num)</code>, which returns the number of bits where both <code>n</code> and <code>num</code> are <code>1</code> in that position of their binary representation. In other words, it returns the number of <span data-keyword="set-bit">set bits</span> in <code>n &amp; num</code>, where <code>&amp;</code> is the bitwise <code>AND</code> operator.</p> <p>Return <em>the number</em> <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 31 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 31 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>31</code> using the provided API.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 33 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 33 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>33</code> using the provided API.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 2<sup>30</sup> - 1</code></li> <li><code>0 &lt;= num &lt;= 2<sup>30</sup> - 1</code></li> <li>If you ask for some <code>num</code> out of the given range, the output wouldn&#39;t be reliable.</li> </ul>
Bit Manipulation; Interactive
C++
/** * Definition of commonSetBits API. * int commonSetBits(int num); */ class Solution { public: int findNumber() { int n = 0; for (int i = 0; i < 32; ++i) { if (commonSetBits(1 << i)) { n |= 1 << i; } } return n; } };
3,064
Guess the Number Using Bitwise Questions I
Medium
<p>There is a number <code>n</code> that you have to find.</p> <p>There is also a pre-defined API <code>int commonSetBits(int num)</code>, which returns the number of bits where both <code>n</code> and <code>num</code> are <code>1</code> in that position of their binary representation. In other words, it returns the number of <span data-keyword="set-bit">set bits</span> in <code>n &amp; num</code>, where <code>&amp;</code> is the bitwise <code>AND</code> operator.</p> <p>Return <em>the number</em> <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 31 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 31 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>31</code> using the provided API.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 33 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 33 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>33</code> using the provided API.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 2<sup>30</sup> - 1</code></li> <li><code>0 &lt;= num &lt;= 2<sup>30</sup> - 1</code></li> <li>If you ask for some <code>num</code> out of the given range, the output wouldn&#39;t be reliable.</li> </ul>
Bit Manipulation; Interactive
Go
/** * Definition of commonSetBits API. * func commonSetBits(num int) int; */ func findNumber() (n int) { for i := 0; i < 32; i++ { if commonSetBits(1<<i) > 0 { n |= 1 << i } } return }
3,064
Guess the Number Using Bitwise Questions I
Medium
<p>There is a number <code>n</code> that you have to find.</p> <p>There is also a pre-defined API <code>int commonSetBits(int num)</code>, which returns the number of bits where both <code>n</code> and <code>num</code> are <code>1</code> in that position of their binary representation. In other words, it returns the number of <span data-keyword="set-bit">set bits</span> in <code>n &amp; num</code>, where <code>&amp;</code> is the bitwise <code>AND</code> operator.</p> <p>Return <em>the number</em> <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 31 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 31 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>31</code> using the provided API.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 33 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 33 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>33</code> using the provided API.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 2<sup>30</sup> - 1</code></li> <li><code>0 &lt;= num &lt;= 2<sup>30</sup> - 1</code></li> <li>If you ask for some <code>num</code> out of the given range, the output wouldn&#39;t be reliable.</li> </ul>
Bit Manipulation; Interactive
Java
/** * Definition of commonSetBits API (defined in the parent class Problem). * int commonSetBits(int num); */ public class Solution extends Problem { public int findNumber() { int n = 0; for (int i = 0; i < 32; ++i) { if (commonSetBits(1 << i) > 0) { n |= 1 << i; } } return n; } }
3,064
Guess the Number Using Bitwise Questions I
Medium
<p>There is a number <code>n</code> that you have to find.</p> <p>There is also a pre-defined API <code>int commonSetBits(int num)</code>, which returns the number of bits where both <code>n</code> and <code>num</code> are <code>1</code> in that position of their binary representation. In other words, it returns the number of <span data-keyword="set-bit">set bits</span> in <code>n &amp; num</code>, where <code>&amp;</code> is the bitwise <code>AND</code> operator.</p> <p>Return <em>the number</em> <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 31 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 31 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>31</code> using the provided API.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 33 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 33 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>33</code> using the provided API.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 2<sup>30</sup> - 1</code></li> <li><code>0 &lt;= num &lt;= 2<sup>30</sup> - 1</code></li> <li>If you ask for some <code>num</code> out of the given range, the output wouldn&#39;t be reliable.</li> </ul>
Bit Manipulation; Interactive
Python
# Definition of commonSetBits API. # def commonSetBits(num: int) -> int: class Solution: def findNumber(self) -> int: return sum(1 << i for i in range(32) if commonSetBits(1 << i))
3,064
Guess the Number Using Bitwise Questions I
Medium
<p>There is a number <code>n</code> that you have to find.</p> <p>There is also a pre-defined API <code>int commonSetBits(int num)</code>, which returns the number of bits where both <code>n</code> and <code>num</code> are <code>1</code> in that position of their binary representation. In other words, it returns the number of <span data-keyword="set-bit">set bits</span> in <code>n &amp; num</code>, where <code>&amp;</code> is the bitwise <code>AND</code> operator.</p> <p>Return <em>the number</em> <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 31 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 31 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>31</code> using the provided API.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> n = 33 </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 33 </span></p> <p><strong>Explanation: </strong> It can be proven that it&#39;s possible to find <code>33</code> using the provided API.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 2<sup>30</sup> - 1</code></li> <li><code>0 &lt;= num &lt;= 2<sup>30</sup> - 1</code></li> <li>If you ask for some <code>num</code> out of the given range, the output wouldn&#39;t be reliable.</li> </ul>
Bit Manipulation; Interactive
TypeScript
/** * Definition of commonSetBits API. * var commonSetBits = function(num: number): number {} */ function findNumber(): number { let n = 0; for (let i = 0; i < 32; ++i) { if (commonSetBits(1 << i)) { n |= 1 << i; } } return n; }
3,065
Minimum Operations to Exceed Threshold Value I
Easy
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>In one operation, you can remove one occurrence of the smallest element of <code>nums</code>.</p> <p>Return <em>the <strong>minimum</strong> number of operations needed so that all elements of the array are greater than or equal to</em> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,11,10,1,3], k = 10 <strong>Output:</strong> 3 <strong>Explanation:</strong> After one operation, nums becomes equal to [2, 11, 10, 3]. After two operations, nums becomes equal to [11, 10, 3]. After three operations, nums becomes equal to [11, 10]. At this stage, all the elements of nums are greater than or equal to 10 so we can stop. It can be shown that 3 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 1 <strong>Output:</strong> 0 <strong>Explanation:</strong> All elements of the array are greater than or equal to 1 so we do not need to apply any operations on nums.</pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 9 <strong>Output:</strong> 4 <strong>Explanation:</strong> only a single element of nums is greater than or equal to 9 so we need to apply the operations 4 times on nums. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that there is at least one index <code>i</code> such that <code>nums[i] &gt;= k</code>.</li> </ul>
Array
C++
class Solution { public: int minOperations(vector<int>& nums, int k) { int ans = 0; for (int x : nums) { if (x < k) { ++ans; } } return ans; } };
3,065
Minimum Operations to Exceed Threshold Value I
Easy
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>In one operation, you can remove one occurrence of the smallest element of <code>nums</code>.</p> <p>Return <em>the <strong>minimum</strong> number of operations needed so that all elements of the array are greater than or equal to</em> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,11,10,1,3], k = 10 <strong>Output:</strong> 3 <strong>Explanation:</strong> After one operation, nums becomes equal to [2, 11, 10, 3]. After two operations, nums becomes equal to [11, 10, 3]. After three operations, nums becomes equal to [11, 10]. At this stage, all the elements of nums are greater than or equal to 10 so we can stop. It can be shown that 3 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 1 <strong>Output:</strong> 0 <strong>Explanation:</strong> All elements of the array are greater than or equal to 1 so we do not need to apply any operations on nums.</pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 9 <strong>Output:</strong> 4 <strong>Explanation:</strong> only a single element of nums is greater than or equal to 9 so we need to apply the operations 4 times on nums. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that there is at least one index <code>i</code> such that <code>nums[i] &gt;= k</code>.</li> </ul>
Array
Go
func minOperations(nums []int, k int) (ans int) { for _, x := range nums { if x < k { ans++ } } return }
3,065
Minimum Operations to Exceed Threshold Value I
Easy
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>In one operation, you can remove one occurrence of the smallest element of <code>nums</code>.</p> <p>Return <em>the <strong>minimum</strong> number of operations needed so that all elements of the array are greater than or equal to</em> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,11,10,1,3], k = 10 <strong>Output:</strong> 3 <strong>Explanation:</strong> After one operation, nums becomes equal to [2, 11, 10, 3]. After two operations, nums becomes equal to [11, 10, 3]. After three operations, nums becomes equal to [11, 10]. At this stage, all the elements of nums are greater than or equal to 10 so we can stop. It can be shown that 3 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 1 <strong>Output:</strong> 0 <strong>Explanation:</strong> All elements of the array are greater than or equal to 1 so we do not need to apply any operations on nums.</pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 9 <strong>Output:</strong> 4 <strong>Explanation:</strong> only a single element of nums is greater than or equal to 9 so we need to apply the operations 4 times on nums. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that there is at least one index <code>i</code> such that <code>nums[i] &gt;= k</code>.</li> </ul>
Array
Java
class Solution { public int minOperations(int[] nums, int k) { int ans = 0; for (int x : nums) { if (x < k) { ++ans; } } return ans; } }
3,065
Minimum Operations to Exceed Threshold Value I
Easy
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>In one operation, you can remove one occurrence of the smallest element of <code>nums</code>.</p> <p>Return <em>the <strong>minimum</strong> number of operations needed so that all elements of the array are greater than or equal to</em> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,11,10,1,3], k = 10 <strong>Output:</strong> 3 <strong>Explanation:</strong> After one operation, nums becomes equal to [2, 11, 10, 3]. After two operations, nums becomes equal to [11, 10, 3]. After three operations, nums becomes equal to [11, 10]. At this stage, all the elements of nums are greater than or equal to 10 so we can stop. It can be shown that 3 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 1 <strong>Output:</strong> 0 <strong>Explanation:</strong> All elements of the array are greater than or equal to 1 so we do not need to apply any operations on nums.</pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 9 <strong>Output:</strong> 4 <strong>Explanation:</strong> only a single element of nums is greater than or equal to 9 so we need to apply the operations 4 times on nums. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that there is at least one index <code>i</code> such that <code>nums[i] &gt;= k</code>.</li> </ul>
Array
Python
class Solution: def minOperations(self, nums: List[int], k: int) -> int: return sum(x < k for x in nums)
3,065
Minimum Operations to Exceed Threshold Value I
Easy
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>In one operation, you can remove one occurrence of the smallest element of <code>nums</code>.</p> <p>Return <em>the <strong>minimum</strong> number of operations needed so that all elements of the array are greater than or equal to</em> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,11,10,1,3], k = 10 <strong>Output:</strong> 3 <strong>Explanation:</strong> After one operation, nums becomes equal to [2, 11, 10, 3]. After two operations, nums becomes equal to [11, 10, 3]. After three operations, nums becomes equal to [11, 10]. At this stage, all the elements of nums are greater than or equal to 10 so we can stop. It can be shown that 3 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 1 <strong>Output:</strong> 0 <strong>Explanation:</strong> All elements of the array are greater than or equal to 1 so we do not need to apply any operations on nums.</pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [1,1,2,4,9], k = 9 <strong>Output:</strong> 4 <strong>Explanation:</strong> only a single element of nums is greater than or equal to 9 so we need to apply the operations 4 times on nums. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that there is at least one index <code>i</code> such that <code>nums[i] &gt;= k</code>.</li> </ul>
Array
TypeScript
function minOperations(nums: number[], k: number): number { return nums.filter(x => x < k).length; }
3,066
Minimum Operations to Exceed Threshold Value II
Medium
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>You are allowed to perform some operations on <code>nums</code>, where in a single operation, you can:</p> <ul> <li>Select the two <strong>smallest</strong> integers <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Remove <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Insert <code>(min(x, y) * 2 + max(x, y))</code> at any position in the array.</li> </ul> <p><strong>Note</strong> that you can only apply the described operation if <code>nums</code> contains <strong>at least</strong> two elements.</p> <p>Return the <strong>minimum</strong> number of operations needed so that all elements of the array are <strong>greater than or equal to</strong> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,11,10,1,3], k = 10</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ol> <li>In the first operation, we remove elements 1 and 2, then add <code>1 * 2 + 2</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[4, 11, 10, 3]</code>.</li> <li>In the second operation, we remove elements 3 and 4, then add <code>3 * 2 + 4</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[10, 11, 10]</code>.</li> </ol> <p>At this stage, all the elements of nums are greater than or equal to 10 so we can stop.&nbsp;</p> <p>It can be shown that 2 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,2,4,9], k = 20</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ol> <li>After one operation, <code>nums</code> becomes equal to <code>[2, 4, 9, 3]</code>.&nbsp;</li> <li>After two operations, <code>nums</code> becomes equal to <code>[7, 4, 9]</code>.&nbsp;</li> <li>After three operations, <code>nums</code> becomes equal to <code>[15, 9]</code>.&nbsp;</li> <li>After four operations, <code>nums</code> becomes equal to <code>[33]</code>.</li> </ol> <p>At this stage, all the elements of <code>nums</code> are greater than 20 so we can stop.&nbsp;</p> <p>It can be shown that 4 is the minimum number of operations needed so that all elements of the array are greater than or equal to 20.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that an answer always exists. That is, after performing some number of operations, all elements of the array are greater than or equal to <code>k</code>.</li> </ul>
Array; Simulation; Heap (Priority Queue)
C++
class Solution { public: int minOperations(vector<int>& nums, int k) { using ll = long long; priority_queue<ll, vector<ll>, greater<ll>> pq; for (int x : nums) { pq.push(x); } int ans = 0; for (; pq.size() > 1 && pq.top() < k; ++ans) { ll x = pq.top(); pq.pop(); ll y = pq.top(); pq.pop(); pq.push(x * 2 + y); } return ans; } };
3,066
Minimum Operations to Exceed Threshold Value II
Medium
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>You are allowed to perform some operations on <code>nums</code>, where in a single operation, you can:</p> <ul> <li>Select the two <strong>smallest</strong> integers <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Remove <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Insert <code>(min(x, y) * 2 + max(x, y))</code> at any position in the array.</li> </ul> <p><strong>Note</strong> that you can only apply the described operation if <code>nums</code> contains <strong>at least</strong> two elements.</p> <p>Return the <strong>minimum</strong> number of operations needed so that all elements of the array are <strong>greater than or equal to</strong> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,11,10,1,3], k = 10</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ol> <li>In the first operation, we remove elements 1 and 2, then add <code>1 * 2 + 2</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[4, 11, 10, 3]</code>.</li> <li>In the second operation, we remove elements 3 and 4, then add <code>3 * 2 + 4</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[10, 11, 10]</code>.</li> </ol> <p>At this stage, all the elements of nums are greater than or equal to 10 so we can stop.&nbsp;</p> <p>It can be shown that 2 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,2,4,9], k = 20</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ol> <li>After one operation, <code>nums</code> becomes equal to <code>[2, 4, 9, 3]</code>.&nbsp;</li> <li>After two operations, <code>nums</code> becomes equal to <code>[7, 4, 9]</code>.&nbsp;</li> <li>After three operations, <code>nums</code> becomes equal to <code>[15, 9]</code>.&nbsp;</li> <li>After four operations, <code>nums</code> becomes equal to <code>[33]</code>.</li> </ol> <p>At this stage, all the elements of <code>nums</code> are greater than 20 so we can stop.&nbsp;</p> <p>It can be shown that 4 is the minimum number of operations needed so that all elements of the array are greater than or equal to 20.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that an answer always exists. That is, after performing some number of operations, all elements of the array are greater than or equal to <code>k</code>.</li> </ul>
Array; Simulation; Heap (Priority Queue)
Go
func minOperations(nums []int, k int) (ans int) { pq := &hp{nums} heap.Init(pq) for ; pq.Len() > 1 && pq.IntSlice[0] < k; ans++ { x, y := heap.Pop(pq).(int), heap.Pop(pq).(int) heap.Push(pq, x*2+y) } return } type hp struct{ sort.IntSlice } func (h *hp) Less(i, j int) bool { return h.IntSlice[i] < h.IntSlice[j] } func (h *hp) Pop() interface{} { old := h.IntSlice n := len(old) x := old[n-1] h.IntSlice = old[0 : n-1] return x } func (h *hp) Push(x interface{}) { h.IntSlice = append(h.IntSlice, x.(int)) }
3,066
Minimum Operations to Exceed Threshold Value II
Medium
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>You are allowed to perform some operations on <code>nums</code>, where in a single operation, you can:</p> <ul> <li>Select the two <strong>smallest</strong> integers <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Remove <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Insert <code>(min(x, y) * 2 + max(x, y))</code> at any position in the array.</li> </ul> <p><strong>Note</strong> that you can only apply the described operation if <code>nums</code> contains <strong>at least</strong> two elements.</p> <p>Return the <strong>minimum</strong> number of operations needed so that all elements of the array are <strong>greater than or equal to</strong> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,11,10,1,3], k = 10</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ol> <li>In the first operation, we remove elements 1 and 2, then add <code>1 * 2 + 2</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[4, 11, 10, 3]</code>.</li> <li>In the second operation, we remove elements 3 and 4, then add <code>3 * 2 + 4</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[10, 11, 10]</code>.</li> </ol> <p>At this stage, all the elements of nums are greater than or equal to 10 so we can stop.&nbsp;</p> <p>It can be shown that 2 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,2,4,9], k = 20</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ol> <li>After one operation, <code>nums</code> becomes equal to <code>[2, 4, 9, 3]</code>.&nbsp;</li> <li>After two operations, <code>nums</code> becomes equal to <code>[7, 4, 9]</code>.&nbsp;</li> <li>After three operations, <code>nums</code> becomes equal to <code>[15, 9]</code>.&nbsp;</li> <li>After four operations, <code>nums</code> becomes equal to <code>[33]</code>.</li> </ol> <p>At this stage, all the elements of <code>nums</code> are greater than 20 so we can stop.&nbsp;</p> <p>It can be shown that 4 is the minimum number of operations needed so that all elements of the array are greater than or equal to 20.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that an answer always exists. That is, after performing some number of operations, all elements of the array are greater than or equal to <code>k</code>.</li> </ul>
Array; Simulation; Heap (Priority Queue)
Java
class Solution { public int minOperations(int[] nums, int k) { PriorityQueue<Long> pq = new PriorityQueue<>(); for (int x : nums) { pq.offer((long) x); } int ans = 0; for (; pq.size() > 1 && pq.peek() < k; ++ans) { long x = pq.poll(), y = pq.poll(); pq.offer(x * 2 + y); } return ans; } }
3,066
Minimum Operations to Exceed Threshold Value II
Medium
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>You are allowed to perform some operations on <code>nums</code>, where in a single operation, you can:</p> <ul> <li>Select the two <strong>smallest</strong> integers <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Remove <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Insert <code>(min(x, y) * 2 + max(x, y))</code> at any position in the array.</li> </ul> <p><strong>Note</strong> that you can only apply the described operation if <code>nums</code> contains <strong>at least</strong> two elements.</p> <p>Return the <strong>minimum</strong> number of operations needed so that all elements of the array are <strong>greater than or equal to</strong> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,11,10,1,3], k = 10</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ol> <li>In the first operation, we remove elements 1 and 2, then add <code>1 * 2 + 2</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[4, 11, 10, 3]</code>.</li> <li>In the second operation, we remove elements 3 and 4, then add <code>3 * 2 + 4</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[10, 11, 10]</code>.</li> </ol> <p>At this stage, all the elements of nums are greater than or equal to 10 so we can stop.&nbsp;</p> <p>It can be shown that 2 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,2,4,9], k = 20</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ol> <li>After one operation, <code>nums</code> becomes equal to <code>[2, 4, 9, 3]</code>.&nbsp;</li> <li>After two operations, <code>nums</code> becomes equal to <code>[7, 4, 9]</code>.&nbsp;</li> <li>After three operations, <code>nums</code> becomes equal to <code>[15, 9]</code>.&nbsp;</li> <li>After four operations, <code>nums</code> becomes equal to <code>[33]</code>.</li> </ol> <p>At this stage, all the elements of <code>nums</code> are greater than 20 so we can stop.&nbsp;</p> <p>It can be shown that 4 is the minimum number of operations needed so that all elements of the array are greater than or equal to 20.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that an answer always exists. That is, after performing some number of operations, all elements of the array are greater than or equal to <code>k</code>.</li> </ul>
Array; Simulation; Heap (Priority Queue)
Python
class Solution: def minOperations(self, nums: List[int], k: int) -> int: heapify(nums) ans = 0 while len(nums) > 1 and nums[0] < k: x, y = heappop(nums), heappop(nums) heappush(nums, x * 2 + y) ans += 1 return ans
3,066
Minimum Operations to Exceed Threshold Value II
Medium
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>You are allowed to perform some operations on <code>nums</code>, where in a single operation, you can:</p> <ul> <li>Select the two <strong>smallest</strong> integers <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Remove <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Insert <code>(min(x, y) * 2 + max(x, y))</code> at any position in the array.</li> </ul> <p><strong>Note</strong> that you can only apply the described operation if <code>nums</code> contains <strong>at least</strong> two elements.</p> <p>Return the <strong>minimum</strong> number of operations needed so that all elements of the array are <strong>greater than or equal to</strong> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,11,10,1,3], k = 10</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ol> <li>In the first operation, we remove elements 1 and 2, then add <code>1 * 2 + 2</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[4, 11, 10, 3]</code>.</li> <li>In the second operation, we remove elements 3 and 4, then add <code>3 * 2 + 4</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[10, 11, 10]</code>.</li> </ol> <p>At this stage, all the elements of nums are greater than or equal to 10 so we can stop.&nbsp;</p> <p>It can be shown that 2 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,2,4,9], k = 20</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ol> <li>After one operation, <code>nums</code> becomes equal to <code>[2, 4, 9, 3]</code>.&nbsp;</li> <li>After two operations, <code>nums</code> becomes equal to <code>[7, 4, 9]</code>.&nbsp;</li> <li>After three operations, <code>nums</code> becomes equal to <code>[15, 9]</code>.&nbsp;</li> <li>After four operations, <code>nums</code> becomes equal to <code>[33]</code>.</li> </ol> <p>At this stage, all the elements of <code>nums</code> are greater than 20 so we can stop.&nbsp;</p> <p>It can be shown that 4 is the minimum number of operations needed so that all elements of the array are greater than or equal to 20.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that an answer always exists. That is, after performing some number of operations, all elements of the array are greater than or equal to <code>k</code>.</li> </ul>
Array; Simulation; Heap (Priority Queue)
Rust
use std::collections::BinaryHeap; impl Solution { pub fn min_operations(nums: Vec<i32>, k: i32) -> i32 { let mut pq = BinaryHeap::new(); for &x in &nums { pq.push(-(x as i64)); } let mut ans = 0; while pq.len() > 1 && -pq.peek().unwrap() < k as i64 { let x = -pq.pop().unwrap(); let y = -pq.pop().unwrap(); pq.push(-(x * 2 + y)); ans += 1; } ans } }
3,066
Minimum Operations to Exceed Threshold Value II
Medium
<p>You are given a <strong>0-indexed</strong> integer array <code>nums</code>, and an integer <code>k</code>.</p> <p>You are allowed to perform some operations on <code>nums</code>, where in a single operation, you can:</p> <ul> <li>Select the two <strong>smallest</strong> integers <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Remove <code>x</code> and <code>y</code> from <code>nums</code>.</li> <li>Insert <code>(min(x, y) * 2 + max(x, y))</code> at any position in the array.</li> </ul> <p><strong>Note</strong> that you can only apply the described operation if <code>nums</code> contains <strong>at least</strong> two elements.</p> <p>Return the <strong>minimum</strong> number of operations needed so that all elements of the array are <strong>greater than or equal to</strong> <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,11,10,1,3], k = 10</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ol> <li>In the first operation, we remove elements 1 and 2, then add <code>1 * 2 + 2</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[4, 11, 10, 3]</code>.</li> <li>In the second operation, we remove elements 3 and 4, then add <code>3 * 2 + 4</code> to <code>nums</code>. <code>nums</code> becomes equal to <code>[10, 11, 10]</code>.</li> </ol> <p>At this stage, all the elements of nums are greater than or equal to 10 so we can stop.&nbsp;</p> <p>It can be shown that 2 is the minimum number of operations needed so that all elements of the array are greater than or equal to 10.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,2,4,9], k = 20</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ol> <li>After one operation, <code>nums</code> becomes equal to <code>[2, 4, 9, 3]</code>.&nbsp;</li> <li>After two operations, <code>nums</code> becomes equal to <code>[7, 4, 9]</code>.&nbsp;</li> <li>After three operations, <code>nums</code> becomes equal to <code>[15, 9]</code>.&nbsp;</li> <li>After four operations, <code>nums</code> becomes equal to <code>[33]</code>.</li> </ol> <p>At this stage, all the elements of <code>nums</code> are greater than 20 so we can stop.&nbsp;</p> <p>It can be shown that 4 is the minimum number of operations needed so that all elements of the array are greater than or equal to 20.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that an answer always exists. That is, after performing some number of operations, all elements of the array are greater than or equal to <code>k</code>.</li> </ul>
Array; Simulation; Heap (Priority Queue)
TypeScript
function minOperations(nums: number[], k: number): number { const pq = new MinPriorityQueue(); for (const x of nums) { pq.enqueue(x); } let ans = 0; for (; pq.size() > 1 && pq.front().element < k; ++ans) { const x = pq.dequeue().element; const y = pq.dequeue().element; pq.enqueue(x * 2 + y); } return ans; }
3,067
Count Pairs of Connectable Servers in a Weighted Tree Network
Medium
<p>You are given an unrooted weighted tree with <code>n</code> vertices representing servers numbered from <code>0</code> to <code>n - 1</code>, an array <code>edges</code> where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code> represents a bidirectional edge between vertices <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> of weight <code>weight<sub>i</sub></code>. You are also given an integer <code>signalSpeed</code>.</p> <p>Two servers <code>a</code> and <code>b</code> are <strong>connectable</strong> through a server <code>c</code> if:</p> <ul> <li><code>a &lt; b</code>, <code>a != c</code> and <code>b != c</code>.</li> <li>The distance from <code>c</code> to <code>a</code> is divisible by <code>signalSpeed</code>.</li> <li>The distance from <code>c</code> to <code>b</code> is divisible by <code>signalSpeed</code>.</li> <li>The path from <code>c</code> to <code>b</code> and the path from <code>c</code> to <code>a</code> do not share any edges.</li> </ul> <p>Return <em>an integer array</em> <code>count</code> <em>of length</em> <code>n</code> <em>where</em> <code>count[i]</code> <em>is the <strong>number</strong> of server pairs that are <strong>connectable</strong> through</em> <em>the server</em> <code>i</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example22.png" style="width: 438px; height: 243px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,1,1],[1,2,5],[2,3,13],[3,4,9],[4,5,2]], signalSpeed = 1 <strong>Output:</strong> [0,4,6,6,4,0] <strong>Explanation:</strong> Since signalSpeed is 1, count[c] is equal to the number of pairs of paths that start at c and do not share any edges. In the case of the given path graph, count[c] is equal to the number of servers to the left of c multiplied by the servers to the right of c. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example11.png" style="width: 495px; height: 484px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,6,3],[6,5,3],[0,3,1],[3,2,7],[3,1,6],[3,4,2]], signalSpeed = 3 <strong>Output:</strong> [2,0,0,0,0,0,2] <strong>Explanation:</strong> Through server 0, there are 2 pairs of connectable servers: (4, 5) and (4, 6). Through server 6, there are 2 pairs of connectable servers: (4, 5) and (0, 5). It can be shown that no two servers are connectable through servers other than 0 and 6. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 1000</code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 3</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li><code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code><!-- notionvc: a2623897-1bb1-4c07-84b6-917ffdcd83ec --></li> <li><code>1 &lt;= weight<sub>i</sub> &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= signalSpeed &lt;= 10<sup>6</sup></code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search; Array
C++
class Solution { public: vector<int> countPairsOfConnectableServers(vector<vector<int>>& edges, int signalSpeed) { int n = edges.size() + 1; vector<pair<int, int>> g[n]; for (auto& e : edges) { int a = e[0], b = e[1], w = e[2]; g[a].emplace_back(b, w); g[b].emplace_back(a, w); } function<int(int, int, int)> dfs = [&](int a, int fa, int ws) { int cnt = ws % signalSpeed == 0; for (auto& [b, w] : g[a]) { if (b != fa) { cnt += dfs(b, a, ws + w); } } return cnt; }; vector<int> ans(n); for (int a = 0; a < n; ++a) { int s = 0; for (auto& [b, w] : g[a]) { int t = dfs(b, a, w); ans[a] += s * t; s += t; } } return ans; } };
3,067
Count Pairs of Connectable Servers in a Weighted Tree Network
Medium
<p>You are given an unrooted weighted tree with <code>n</code> vertices representing servers numbered from <code>0</code> to <code>n - 1</code>, an array <code>edges</code> where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code> represents a bidirectional edge between vertices <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> of weight <code>weight<sub>i</sub></code>. You are also given an integer <code>signalSpeed</code>.</p> <p>Two servers <code>a</code> and <code>b</code> are <strong>connectable</strong> through a server <code>c</code> if:</p> <ul> <li><code>a &lt; b</code>, <code>a != c</code> and <code>b != c</code>.</li> <li>The distance from <code>c</code> to <code>a</code> is divisible by <code>signalSpeed</code>.</li> <li>The distance from <code>c</code> to <code>b</code> is divisible by <code>signalSpeed</code>.</li> <li>The path from <code>c</code> to <code>b</code> and the path from <code>c</code> to <code>a</code> do not share any edges.</li> </ul> <p>Return <em>an integer array</em> <code>count</code> <em>of length</em> <code>n</code> <em>where</em> <code>count[i]</code> <em>is the <strong>number</strong> of server pairs that are <strong>connectable</strong> through</em> <em>the server</em> <code>i</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example22.png" style="width: 438px; height: 243px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,1,1],[1,2,5],[2,3,13],[3,4,9],[4,5,2]], signalSpeed = 1 <strong>Output:</strong> [0,4,6,6,4,0] <strong>Explanation:</strong> Since signalSpeed is 1, count[c] is equal to the number of pairs of paths that start at c and do not share any edges. In the case of the given path graph, count[c] is equal to the number of servers to the left of c multiplied by the servers to the right of c. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example11.png" style="width: 495px; height: 484px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,6,3],[6,5,3],[0,3,1],[3,2,7],[3,1,6],[3,4,2]], signalSpeed = 3 <strong>Output:</strong> [2,0,0,0,0,0,2] <strong>Explanation:</strong> Through server 0, there are 2 pairs of connectable servers: (4, 5) and (4, 6). Through server 6, there are 2 pairs of connectable servers: (4, 5) and (0, 5). It can be shown that no two servers are connectable through servers other than 0 and 6. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 1000</code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 3</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li><code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code><!-- notionvc: a2623897-1bb1-4c07-84b6-917ffdcd83ec --></li> <li><code>1 &lt;= weight<sub>i</sub> &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= signalSpeed &lt;= 10<sup>6</sup></code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search; Array
Go
func countPairsOfConnectableServers(edges [][]int, signalSpeed int) []int { n := len(edges) + 1 type pair struct{ x, w int } g := make([][]pair, n) for _, e := range edges { a, b, w := e[0], e[1], e[2] g[a] = append(g[a], pair{b, w}) g[b] = append(g[b], pair{a, w}) } var dfs func(a, fa, ws int) int dfs = func(a, fa, ws int) int { cnt := 0 if ws%signalSpeed == 0 { cnt++ } for _, e := range g[a] { b, w := e.x, e.w if b != fa { cnt += dfs(b, a, ws+w) } } return cnt } ans := make([]int, n) for a := 0; a < n; a++ { s := 0 for _, e := range g[a] { b, w := e.x, e.w t := dfs(b, a, w) ans[a] += s * t s += t } } return ans }
3,067
Count Pairs of Connectable Servers in a Weighted Tree Network
Medium
<p>You are given an unrooted weighted tree with <code>n</code> vertices representing servers numbered from <code>0</code> to <code>n - 1</code>, an array <code>edges</code> where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code> represents a bidirectional edge between vertices <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> of weight <code>weight<sub>i</sub></code>. You are also given an integer <code>signalSpeed</code>.</p> <p>Two servers <code>a</code> and <code>b</code> are <strong>connectable</strong> through a server <code>c</code> if:</p> <ul> <li><code>a &lt; b</code>, <code>a != c</code> and <code>b != c</code>.</li> <li>The distance from <code>c</code> to <code>a</code> is divisible by <code>signalSpeed</code>.</li> <li>The distance from <code>c</code> to <code>b</code> is divisible by <code>signalSpeed</code>.</li> <li>The path from <code>c</code> to <code>b</code> and the path from <code>c</code> to <code>a</code> do not share any edges.</li> </ul> <p>Return <em>an integer array</em> <code>count</code> <em>of length</em> <code>n</code> <em>where</em> <code>count[i]</code> <em>is the <strong>number</strong> of server pairs that are <strong>connectable</strong> through</em> <em>the server</em> <code>i</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example22.png" style="width: 438px; height: 243px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,1,1],[1,2,5],[2,3,13],[3,4,9],[4,5,2]], signalSpeed = 1 <strong>Output:</strong> [0,4,6,6,4,0] <strong>Explanation:</strong> Since signalSpeed is 1, count[c] is equal to the number of pairs of paths that start at c and do not share any edges. In the case of the given path graph, count[c] is equal to the number of servers to the left of c multiplied by the servers to the right of c. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example11.png" style="width: 495px; height: 484px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,6,3],[6,5,3],[0,3,1],[3,2,7],[3,1,6],[3,4,2]], signalSpeed = 3 <strong>Output:</strong> [2,0,0,0,0,0,2] <strong>Explanation:</strong> Through server 0, there are 2 pairs of connectable servers: (4, 5) and (4, 6). Through server 6, there are 2 pairs of connectable servers: (4, 5) and (0, 5). It can be shown that no two servers are connectable through servers other than 0 and 6. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 1000</code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 3</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li><code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code><!-- notionvc: a2623897-1bb1-4c07-84b6-917ffdcd83ec --></li> <li><code>1 &lt;= weight<sub>i</sub> &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= signalSpeed &lt;= 10<sup>6</sup></code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search; Array
Java
class Solution { private int signalSpeed; private List<int[]>[] g; public int[] countPairsOfConnectableServers(int[][] edges, int signalSpeed) { int n = edges.length + 1; g = new List[n]; this.signalSpeed = signalSpeed; Arrays.setAll(g, k -> new ArrayList<>()); for (var e : edges) { int a = e[0], b = e[1], w = e[2]; g[a].add(new int[] {b, w}); g[b].add(new int[] {a, w}); } int[] ans = new int[n]; for (int a = 0; a < n; ++a) { int s = 0; for (var e : g[a]) { int b = e[0], w = e[1]; int t = dfs(b, a, w); ans[a] += s * t; s += t; } } return ans; } private int dfs(int a, int fa, int ws) { int cnt = ws % signalSpeed == 0 ? 1 : 0; for (var e : g[a]) { int b = e[0], w = e[1]; if (b != fa) { cnt += dfs(b, a, ws + w); } } return cnt; } }
3,067
Count Pairs of Connectable Servers in a Weighted Tree Network
Medium
<p>You are given an unrooted weighted tree with <code>n</code> vertices representing servers numbered from <code>0</code> to <code>n - 1</code>, an array <code>edges</code> where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code> represents a bidirectional edge between vertices <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> of weight <code>weight<sub>i</sub></code>. You are also given an integer <code>signalSpeed</code>.</p> <p>Two servers <code>a</code> and <code>b</code> are <strong>connectable</strong> through a server <code>c</code> if:</p> <ul> <li><code>a &lt; b</code>, <code>a != c</code> and <code>b != c</code>.</li> <li>The distance from <code>c</code> to <code>a</code> is divisible by <code>signalSpeed</code>.</li> <li>The distance from <code>c</code> to <code>b</code> is divisible by <code>signalSpeed</code>.</li> <li>The path from <code>c</code> to <code>b</code> and the path from <code>c</code> to <code>a</code> do not share any edges.</li> </ul> <p>Return <em>an integer array</em> <code>count</code> <em>of length</em> <code>n</code> <em>where</em> <code>count[i]</code> <em>is the <strong>number</strong> of server pairs that are <strong>connectable</strong> through</em> <em>the server</em> <code>i</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example22.png" style="width: 438px; height: 243px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,1,1],[1,2,5],[2,3,13],[3,4,9],[4,5,2]], signalSpeed = 1 <strong>Output:</strong> [0,4,6,6,4,0] <strong>Explanation:</strong> Since signalSpeed is 1, count[c] is equal to the number of pairs of paths that start at c and do not share any edges. In the case of the given path graph, count[c] is equal to the number of servers to the left of c multiplied by the servers to the right of c. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example11.png" style="width: 495px; height: 484px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,6,3],[6,5,3],[0,3,1],[3,2,7],[3,1,6],[3,4,2]], signalSpeed = 3 <strong>Output:</strong> [2,0,0,0,0,0,2] <strong>Explanation:</strong> Through server 0, there are 2 pairs of connectable servers: (4, 5) and (4, 6). Through server 6, there are 2 pairs of connectable servers: (4, 5) and (0, 5). It can be shown that no two servers are connectable through servers other than 0 and 6. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 1000</code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 3</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li><code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code><!-- notionvc: a2623897-1bb1-4c07-84b6-917ffdcd83ec --></li> <li><code>1 &lt;= weight<sub>i</sub> &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= signalSpeed &lt;= 10<sup>6</sup></code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search; Array
Python
class Solution: def countPairsOfConnectableServers( self, edges: List[List[int]], signalSpeed: int ) -> List[int]: def dfs(a: int, fa: int, ws: int) -> int: cnt = 0 if ws % signalSpeed else 1 for b, w in g[a]: if b != fa: cnt += dfs(b, a, ws + w) return cnt n = len(edges) + 1 g = [[] for _ in range(n)] for a, b, w in edges: g[a].append((b, w)) g[b].append((a, w)) ans = [0] * n for a in range(n): s = 0 for b, w in g[a]: t = dfs(b, a, w) ans[a] += s * t s += t return ans
3,067
Count Pairs of Connectable Servers in a Weighted Tree Network
Medium
<p>You are given an unrooted weighted tree with <code>n</code> vertices representing servers numbered from <code>0</code> to <code>n - 1</code>, an array <code>edges</code> where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code> represents a bidirectional edge between vertices <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> of weight <code>weight<sub>i</sub></code>. You are also given an integer <code>signalSpeed</code>.</p> <p>Two servers <code>a</code> and <code>b</code> are <strong>connectable</strong> through a server <code>c</code> if:</p> <ul> <li><code>a &lt; b</code>, <code>a != c</code> and <code>b != c</code>.</li> <li>The distance from <code>c</code> to <code>a</code> is divisible by <code>signalSpeed</code>.</li> <li>The distance from <code>c</code> to <code>b</code> is divisible by <code>signalSpeed</code>.</li> <li>The path from <code>c</code> to <code>b</code> and the path from <code>c</code> to <code>a</code> do not share any edges.</li> </ul> <p>Return <em>an integer array</em> <code>count</code> <em>of length</em> <code>n</code> <em>where</em> <code>count[i]</code> <em>is the <strong>number</strong> of server pairs that are <strong>connectable</strong> through</em> <em>the server</em> <code>i</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example22.png" style="width: 438px; height: 243px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,1,1],[1,2,5],[2,3,13],[3,4,9],[4,5,2]], signalSpeed = 1 <strong>Output:</strong> [0,4,6,6,4,0] <strong>Explanation:</strong> Since signalSpeed is 1, count[c] is equal to the number of pairs of paths that start at c and do not share any edges. In the case of the given path graph, count[c] is equal to the number of servers to the left of c multiplied by the servers to the right of c. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3067.Count%20Pairs%20of%20Connectable%20Servers%20in%20a%20Weighted%20Tree%20Network/images/example11.png" style="width: 495px; height: 484px; padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> edges = [[0,6,3],[6,5,3],[0,3,1],[3,2,7],[3,1,6],[3,4,2]], signalSpeed = 3 <strong>Output:</strong> [2,0,0,0,0,0,2] <strong>Explanation:</strong> Through server 0, there are 2 pairs of connectable servers: (4, 5) and (4, 6). Through server 6, there are 2 pairs of connectable servers: (4, 5) and (0, 5). It can be shown that no two servers are connectable through servers other than 0 and 6. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 1000</code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 3</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li><code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>, weight<sub>i</sub>]</code><!-- notionvc: a2623897-1bb1-4c07-84b6-917ffdcd83ec --></li> <li><code>1 &lt;= weight<sub>i</sub> &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= signalSpeed &lt;= 10<sup>6</sup></code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search; Array
TypeScript
function countPairsOfConnectableServers(edges: number[][], signalSpeed: number): number[] { const n = edges.length + 1; const g: [number, number][][] = Array.from({ length: n }, () => []); for (const [a, b, w] of edges) { g[a].push([b, w]); g[b].push([a, w]); } const dfs = (a: number, fa: number, ws: number): number => { let cnt = ws % signalSpeed === 0 ? 1 : 0; for (const [b, w] of g[a]) { if (b != fa) { cnt += dfs(b, a, ws + w); } } return cnt; }; const ans: number[] = Array(n).fill(0); for (let a = 0; a < n; ++a) { let s = 0; for (const [b, w] of g[a]) { const t = dfs(b, a, w); ans[a] += s * t; s += t; } } return ans; }
3,068
Find the Maximum Sum of Node Values
Hard
<p>There exists an <strong>undirected</strong> tree with <code>n</code> nodes numbered <code>0</code> to <code>n - 1</code>. You are given a <strong>0-indexed</strong> 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [u<sub>i</sub>, v<sub>i</sub>]</code> indicates that there is an edge between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the tree. You are also given a <strong>positive</strong> integer <code>k</code>, and a <strong>0-indexed</strong> array of <strong>non-negative</strong> integers <code>nums</code> of length <code>n</code>, where <code>nums[i]</code> represents the <strong>value</strong> of the node numbered <code>i</code>.</p> <p>Alice wants the sum of values of tree nodes to be <strong>maximum</strong>, for which Alice can perform the following operation <strong>any</strong> number of times (<strong>including zero</strong>) on the tree:</p> <ul> <li>Choose any edge <code>[u, v]</code> connecting the nodes <code>u</code> and <code>v</code>, and update their values as follows: <ul> <li><code>nums[u] = nums[u] XOR k</code></li> <li><code>nums[v] = nums[v] XOR k</code></li> </ul> </li> </ul> <p>Return <em>the <strong>maximum</strong> possible <strong>sum</strong> of the <strong>values</strong> Alice can achieve by performing the operation <strong>any</strong> number of times</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012513.png" style="width: 300px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [1,2,1], k = 3, edges = [[0,1],[0,2]] <strong>Output:</strong> 6 <strong>Explanation:</strong> Alice can achieve the maximum sum of 6 using a single operation: - Choose the edge [0,2]. nums[0] and nums[2] become: 1 XOR 3 = 2, and the array nums becomes: [1,2,1] -&gt; [2,2,2]. The total sum of values is 2 + 2 + 2 = 6. It can be shown that 6 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2024-01-09-220017.png" style="padding: 10px; background: rgb(255, 255, 255); border-radius: 0.5rem; width: 300px; height: 239px;" /> <pre> <strong>Input:</strong> nums = [2,3], k = 7, edges = [[0,1]] <strong>Output:</strong> 9 <strong>Explanation:</strong> Alice can achieve the maximum sum of 9 using a single operation: - Choose the edge [0,1]. nums[0] becomes: 2 XOR 7 = 5 and nums[1] become: 3 XOR 7 = 4, and the array nums becomes: [2,3] -&gt; [5,4]. The total sum of values is 5 + 4 = 9. It can be shown that 9 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012641.png" style="width: 600px; height: 233px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [7,7,7,7,7,7], k = 3, edges = [[0,1],[0,2],[0,3],[0,4],[0,5]] <strong>Output:</strong> 42 <strong>Explanation:</strong> The maximum achievable sum is 42 which can be achieved by Alice performing no operations. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 2 * 10<sup>4</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= edges[i][0], edges[i][1] &lt;= n - 1</code></li> <li>The input is generated such that <code>edges</code> represent&nbsp;a valid tree.</li> </ul>
Greedy; Bit Manipulation; Tree; Array; Dynamic Programming; Sorting
C++
class Solution { public: long long maximumValueSum(vector<int>& nums, int k, vector<vector<int>>& edges) { long long f0 = 0, f1 = -0x3f3f3f3f; for (int x : nums) { long long tmp = f0; f0 = max(f0 + x, f1 + (x ^ k)); f1 = max(f1 + x, tmp + (x ^ k)); } return f0; } };
3,068
Find the Maximum Sum of Node Values
Hard
<p>There exists an <strong>undirected</strong> tree with <code>n</code> nodes numbered <code>0</code> to <code>n - 1</code>. You are given a <strong>0-indexed</strong> 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [u<sub>i</sub>, v<sub>i</sub>]</code> indicates that there is an edge between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the tree. You are also given a <strong>positive</strong> integer <code>k</code>, and a <strong>0-indexed</strong> array of <strong>non-negative</strong> integers <code>nums</code> of length <code>n</code>, where <code>nums[i]</code> represents the <strong>value</strong> of the node numbered <code>i</code>.</p> <p>Alice wants the sum of values of tree nodes to be <strong>maximum</strong>, for which Alice can perform the following operation <strong>any</strong> number of times (<strong>including zero</strong>) on the tree:</p> <ul> <li>Choose any edge <code>[u, v]</code> connecting the nodes <code>u</code> and <code>v</code>, and update their values as follows: <ul> <li><code>nums[u] = nums[u] XOR k</code></li> <li><code>nums[v] = nums[v] XOR k</code></li> </ul> </li> </ul> <p>Return <em>the <strong>maximum</strong> possible <strong>sum</strong> of the <strong>values</strong> Alice can achieve by performing the operation <strong>any</strong> number of times</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012513.png" style="width: 300px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [1,2,1], k = 3, edges = [[0,1],[0,2]] <strong>Output:</strong> 6 <strong>Explanation:</strong> Alice can achieve the maximum sum of 6 using a single operation: - Choose the edge [0,2]. nums[0] and nums[2] become: 1 XOR 3 = 2, and the array nums becomes: [1,2,1] -&gt; [2,2,2]. The total sum of values is 2 + 2 + 2 = 6. It can be shown that 6 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2024-01-09-220017.png" style="padding: 10px; background: rgb(255, 255, 255); border-radius: 0.5rem; width: 300px; height: 239px;" /> <pre> <strong>Input:</strong> nums = [2,3], k = 7, edges = [[0,1]] <strong>Output:</strong> 9 <strong>Explanation:</strong> Alice can achieve the maximum sum of 9 using a single operation: - Choose the edge [0,1]. nums[0] becomes: 2 XOR 7 = 5 and nums[1] become: 3 XOR 7 = 4, and the array nums becomes: [2,3] -&gt; [5,4]. The total sum of values is 5 + 4 = 9. It can be shown that 9 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012641.png" style="width: 600px; height: 233px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [7,7,7,7,7,7], k = 3, edges = [[0,1],[0,2],[0,3],[0,4],[0,5]] <strong>Output:</strong> 42 <strong>Explanation:</strong> The maximum achievable sum is 42 which can be achieved by Alice performing no operations. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 2 * 10<sup>4</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= edges[i][0], edges[i][1] &lt;= n - 1</code></li> <li>The input is generated such that <code>edges</code> represent&nbsp;a valid tree.</li> </ul>
Greedy; Bit Manipulation; Tree; Array; Dynamic Programming; Sorting
C#
public class Solution { public long MaximumValueSum(int[] nums, int k, int[][] edges) { long f0 = 0, f1 = -0x3f3f3f3f; foreach (int x in nums) { long tmp = f0; f0 = Math.Max(f0 + x, f1 + (x ^ k)); f1 = Math.Max(f1 + x, tmp + (x ^ k)); } return f0; } }
3,068
Find the Maximum Sum of Node Values
Hard
<p>There exists an <strong>undirected</strong> tree with <code>n</code> nodes numbered <code>0</code> to <code>n - 1</code>. You are given a <strong>0-indexed</strong> 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [u<sub>i</sub>, v<sub>i</sub>]</code> indicates that there is an edge between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the tree. You are also given a <strong>positive</strong> integer <code>k</code>, and a <strong>0-indexed</strong> array of <strong>non-negative</strong> integers <code>nums</code> of length <code>n</code>, where <code>nums[i]</code> represents the <strong>value</strong> of the node numbered <code>i</code>.</p> <p>Alice wants the sum of values of tree nodes to be <strong>maximum</strong>, for which Alice can perform the following operation <strong>any</strong> number of times (<strong>including zero</strong>) on the tree:</p> <ul> <li>Choose any edge <code>[u, v]</code> connecting the nodes <code>u</code> and <code>v</code>, and update their values as follows: <ul> <li><code>nums[u] = nums[u] XOR k</code></li> <li><code>nums[v] = nums[v] XOR k</code></li> </ul> </li> </ul> <p>Return <em>the <strong>maximum</strong> possible <strong>sum</strong> of the <strong>values</strong> Alice can achieve by performing the operation <strong>any</strong> number of times</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012513.png" style="width: 300px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [1,2,1], k = 3, edges = [[0,1],[0,2]] <strong>Output:</strong> 6 <strong>Explanation:</strong> Alice can achieve the maximum sum of 6 using a single operation: - Choose the edge [0,2]. nums[0] and nums[2] become: 1 XOR 3 = 2, and the array nums becomes: [1,2,1] -&gt; [2,2,2]. The total sum of values is 2 + 2 + 2 = 6. It can be shown that 6 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2024-01-09-220017.png" style="padding: 10px; background: rgb(255, 255, 255); border-radius: 0.5rem; width: 300px; height: 239px;" /> <pre> <strong>Input:</strong> nums = [2,3], k = 7, edges = [[0,1]] <strong>Output:</strong> 9 <strong>Explanation:</strong> Alice can achieve the maximum sum of 9 using a single operation: - Choose the edge [0,1]. nums[0] becomes: 2 XOR 7 = 5 and nums[1] become: 3 XOR 7 = 4, and the array nums becomes: [2,3] -&gt; [5,4]. The total sum of values is 5 + 4 = 9. It can be shown that 9 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012641.png" style="width: 600px; height: 233px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [7,7,7,7,7,7], k = 3, edges = [[0,1],[0,2],[0,3],[0,4],[0,5]] <strong>Output:</strong> 42 <strong>Explanation:</strong> The maximum achievable sum is 42 which can be achieved by Alice performing no operations. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 2 * 10<sup>4</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= edges[i][0], edges[i][1] &lt;= n - 1</code></li> <li>The input is generated such that <code>edges</code> represent&nbsp;a valid tree.</li> </ul>
Greedy; Bit Manipulation; Tree; Array; Dynamic Programming; Sorting
Go
func maximumValueSum(nums []int, k int, edges [][]int) int64 { f0, f1 := 0, -0x3f3f3f3f for _, x := range nums { f0, f1 = max(f0+x, f1+(x^k)), max(f1+x, f0+(x^k)) } return int64(f0) }
3,068
Find the Maximum Sum of Node Values
Hard
<p>There exists an <strong>undirected</strong> tree with <code>n</code> nodes numbered <code>0</code> to <code>n - 1</code>. You are given a <strong>0-indexed</strong> 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [u<sub>i</sub>, v<sub>i</sub>]</code> indicates that there is an edge between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the tree. You are also given a <strong>positive</strong> integer <code>k</code>, and a <strong>0-indexed</strong> array of <strong>non-negative</strong> integers <code>nums</code> of length <code>n</code>, where <code>nums[i]</code> represents the <strong>value</strong> of the node numbered <code>i</code>.</p> <p>Alice wants the sum of values of tree nodes to be <strong>maximum</strong>, for which Alice can perform the following operation <strong>any</strong> number of times (<strong>including zero</strong>) on the tree:</p> <ul> <li>Choose any edge <code>[u, v]</code> connecting the nodes <code>u</code> and <code>v</code>, and update their values as follows: <ul> <li><code>nums[u] = nums[u] XOR k</code></li> <li><code>nums[v] = nums[v] XOR k</code></li> </ul> </li> </ul> <p>Return <em>the <strong>maximum</strong> possible <strong>sum</strong> of the <strong>values</strong> Alice can achieve by performing the operation <strong>any</strong> number of times</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012513.png" style="width: 300px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [1,2,1], k = 3, edges = [[0,1],[0,2]] <strong>Output:</strong> 6 <strong>Explanation:</strong> Alice can achieve the maximum sum of 6 using a single operation: - Choose the edge [0,2]. nums[0] and nums[2] become: 1 XOR 3 = 2, and the array nums becomes: [1,2,1] -&gt; [2,2,2]. The total sum of values is 2 + 2 + 2 = 6. It can be shown that 6 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2024-01-09-220017.png" style="padding: 10px; background: rgb(255, 255, 255); border-radius: 0.5rem; width: 300px; height: 239px;" /> <pre> <strong>Input:</strong> nums = [2,3], k = 7, edges = [[0,1]] <strong>Output:</strong> 9 <strong>Explanation:</strong> Alice can achieve the maximum sum of 9 using a single operation: - Choose the edge [0,1]. nums[0] becomes: 2 XOR 7 = 5 and nums[1] become: 3 XOR 7 = 4, and the array nums becomes: [2,3] -&gt; [5,4]. The total sum of values is 5 + 4 = 9. It can be shown that 9 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012641.png" style="width: 600px; height: 233px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [7,7,7,7,7,7], k = 3, edges = [[0,1],[0,2],[0,3],[0,4],[0,5]] <strong>Output:</strong> 42 <strong>Explanation:</strong> The maximum achievable sum is 42 which can be achieved by Alice performing no operations. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 2 * 10<sup>4</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= edges[i][0], edges[i][1] &lt;= n - 1</code></li> <li>The input is generated such that <code>edges</code> represent&nbsp;a valid tree.</li> </ul>
Greedy; Bit Manipulation; Tree; Array; Dynamic Programming; Sorting
Java
class Solution { public long maximumValueSum(int[] nums, int k, int[][] edges) { long f0 = 0, f1 = -0x3f3f3f3f; for (int x : nums) { long tmp = f0; f0 = Math.max(f0 + x, f1 + (x ^ k)); f1 = Math.max(f1 + x, tmp + (x ^ k)); } return f0; } }
3,068
Find the Maximum Sum of Node Values
Hard
<p>There exists an <strong>undirected</strong> tree with <code>n</code> nodes numbered <code>0</code> to <code>n - 1</code>. You are given a <strong>0-indexed</strong> 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [u<sub>i</sub>, v<sub>i</sub>]</code> indicates that there is an edge between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the tree. You are also given a <strong>positive</strong> integer <code>k</code>, and a <strong>0-indexed</strong> array of <strong>non-negative</strong> integers <code>nums</code> of length <code>n</code>, where <code>nums[i]</code> represents the <strong>value</strong> of the node numbered <code>i</code>.</p> <p>Alice wants the sum of values of tree nodes to be <strong>maximum</strong>, for which Alice can perform the following operation <strong>any</strong> number of times (<strong>including zero</strong>) on the tree:</p> <ul> <li>Choose any edge <code>[u, v]</code> connecting the nodes <code>u</code> and <code>v</code>, and update their values as follows: <ul> <li><code>nums[u] = nums[u] XOR k</code></li> <li><code>nums[v] = nums[v] XOR k</code></li> </ul> </li> </ul> <p>Return <em>the <strong>maximum</strong> possible <strong>sum</strong> of the <strong>values</strong> Alice can achieve by performing the operation <strong>any</strong> number of times</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012513.png" style="width: 300px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [1,2,1], k = 3, edges = [[0,1],[0,2]] <strong>Output:</strong> 6 <strong>Explanation:</strong> Alice can achieve the maximum sum of 6 using a single operation: - Choose the edge [0,2]. nums[0] and nums[2] become: 1 XOR 3 = 2, and the array nums becomes: [1,2,1] -&gt; [2,2,2]. The total sum of values is 2 + 2 + 2 = 6. It can be shown that 6 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2024-01-09-220017.png" style="padding: 10px; background: rgb(255, 255, 255); border-radius: 0.5rem; width: 300px; height: 239px;" /> <pre> <strong>Input:</strong> nums = [2,3], k = 7, edges = [[0,1]] <strong>Output:</strong> 9 <strong>Explanation:</strong> Alice can achieve the maximum sum of 9 using a single operation: - Choose the edge [0,1]. nums[0] becomes: 2 XOR 7 = 5 and nums[1] become: 3 XOR 7 = 4, and the array nums becomes: [2,3] -&gt; [5,4]. The total sum of values is 5 + 4 = 9. It can be shown that 9 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012641.png" style="width: 600px; height: 233px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [7,7,7,7,7,7], k = 3, edges = [[0,1],[0,2],[0,3],[0,4],[0,5]] <strong>Output:</strong> 42 <strong>Explanation:</strong> The maximum achievable sum is 42 which can be achieved by Alice performing no operations. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 2 * 10<sup>4</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= edges[i][0], edges[i][1] &lt;= n - 1</code></li> <li>The input is generated such that <code>edges</code> represent&nbsp;a valid tree.</li> </ul>
Greedy; Bit Manipulation; Tree; Array; Dynamic Programming; Sorting
Python
class Solution: def maximumValueSum(self, nums: List[int], k: int, edges: List[List[int]]) -> int: f0, f1 = 0, -inf for x in nums: f0, f1 = max(f0 + x, f1 + (x ^ k)), max(f1 + x, f0 + (x ^ k)) return f0
3,068
Find the Maximum Sum of Node Values
Hard
<p>There exists an <strong>undirected</strong> tree with <code>n</code> nodes numbered <code>0</code> to <code>n - 1</code>. You are given a <strong>0-indexed</strong> 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [u<sub>i</sub>, v<sub>i</sub>]</code> indicates that there is an edge between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the tree. You are also given a <strong>positive</strong> integer <code>k</code>, and a <strong>0-indexed</strong> array of <strong>non-negative</strong> integers <code>nums</code> of length <code>n</code>, where <code>nums[i]</code> represents the <strong>value</strong> of the node numbered <code>i</code>.</p> <p>Alice wants the sum of values of tree nodes to be <strong>maximum</strong>, for which Alice can perform the following operation <strong>any</strong> number of times (<strong>including zero</strong>) on the tree:</p> <ul> <li>Choose any edge <code>[u, v]</code> connecting the nodes <code>u</code> and <code>v</code>, and update their values as follows: <ul> <li><code>nums[u] = nums[u] XOR k</code></li> <li><code>nums[v] = nums[v] XOR k</code></li> </ul> </li> </ul> <p>Return <em>the <strong>maximum</strong> possible <strong>sum</strong> of the <strong>values</strong> Alice can achieve by performing the operation <strong>any</strong> number of times</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012513.png" style="width: 300px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [1,2,1], k = 3, edges = [[0,1],[0,2]] <strong>Output:</strong> 6 <strong>Explanation:</strong> Alice can achieve the maximum sum of 6 using a single operation: - Choose the edge [0,2]. nums[0] and nums[2] become: 1 XOR 3 = 2, and the array nums becomes: [1,2,1] -&gt; [2,2,2]. The total sum of values is 2 + 2 + 2 = 6. It can be shown that 6 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2024-01-09-220017.png" style="padding: 10px; background: rgb(255, 255, 255); border-radius: 0.5rem; width: 300px; height: 239px;" /> <pre> <strong>Input:</strong> nums = [2,3], k = 7, edges = [[0,1]] <strong>Output:</strong> 9 <strong>Explanation:</strong> Alice can achieve the maximum sum of 9 using a single operation: - Choose the edge [0,1]. nums[0] becomes: 2 XOR 7 = 5 and nums[1] become: 3 XOR 7 = 4, and the array nums becomes: [2,3] -&gt; [5,4]. The total sum of values is 5 + 4 = 9. It can be shown that 9 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012641.png" style="width: 600px; height: 233px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [7,7,7,7,7,7], k = 3, edges = [[0,1],[0,2],[0,3],[0,4],[0,5]] <strong>Output:</strong> 42 <strong>Explanation:</strong> The maximum achievable sum is 42 which can be achieved by Alice performing no operations. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 2 * 10<sup>4</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= edges[i][0], edges[i][1] &lt;= n - 1</code></li> <li>The input is generated such that <code>edges</code> represent&nbsp;a valid tree.</li> </ul>
Greedy; Bit Manipulation; Tree; Array; Dynamic Programming; Sorting
Rust
impl Solution { pub fn maximum_value_sum(nums: Vec<i32>, k: i32, edges: Vec<Vec<i32>>) -> i64 { let mut f0: i64 = 0; let mut f1: i64 = i64::MIN; for &x in &nums { let tmp = f0; f0 = std::cmp::max(f0 + x as i64, f1 + (x ^ k) as i64); f1 = std::cmp::max(f1 + x as i64, tmp + (x ^ k) as i64); } f0 } }
3,068
Find the Maximum Sum of Node Values
Hard
<p>There exists an <strong>undirected</strong> tree with <code>n</code> nodes numbered <code>0</code> to <code>n - 1</code>. You are given a <strong>0-indexed</strong> 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [u<sub>i</sub>, v<sub>i</sub>]</code> indicates that there is an edge between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the tree. You are also given a <strong>positive</strong> integer <code>k</code>, and a <strong>0-indexed</strong> array of <strong>non-negative</strong> integers <code>nums</code> of length <code>n</code>, where <code>nums[i]</code> represents the <strong>value</strong> of the node numbered <code>i</code>.</p> <p>Alice wants the sum of values of tree nodes to be <strong>maximum</strong>, for which Alice can perform the following operation <strong>any</strong> number of times (<strong>including zero</strong>) on the tree:</p> <ul> <li>Choose any edge <code>[u, v]</code> connecting the nodes <code>u</code> and <code>v</code>, and update their values as follows: <ul> <li><code>nums[u] = nums[u] XOR k</code></li> <li><code>nums[v] = nums[v] XOR k</code></li> </ul> </li> </ul> <p>Return <em>the <strong>maximum</strong> possible <strong>sum</strong> of the <strong>values</strong> Alice can achieve by performing the operation <strong>any</strong> number of times</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012513.png" style="width: 300px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [1,2,1], k = 3, edges = [[0,1],[0,2]] <strong>Output:</strong> 6 <strong>Explanation:</strong> Alice can achieve the maximum sum of 6 using a single operation: - Choose the edge [0,2]. nums[0] and nums[2] become: 1 XOR 3 = 2, and the array nums becomes: [1,2,1] -&gt; [2,2,2]. The total sum of values is 2 + 2 + 2 = 6. It can be shown that 6 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2024-01-09-220017.png" style="padding: 10px; background: rgb(255, 255, 255); border-radius: 0.5rem; width: 300px; height: 239px;" /> <pre> <strong>Input:</strong> nums = [2,3], k = 7, edges = [[0,1]] <strong>Output:</strong> 9 <strong>Explanation:</strong> Alice can achieve the maximum sum of 9 using a single operation: - Choose the edge [0,1]. nums[0] becomes: 2 XOR 7 = 5 and nums[1] become: 3 XOR 7 = 4, and the array nums becomes: [2,3] -&gt; [5,4]. The total sum of values is 5 + 4 = 9. It can be shown that 9 is the maximum achievable sum of values. </pre> <p><strong class="example">Example 3:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3068.Find%20the%20Maximum%20Sum%20of%20Node%20Values/images/screenshot-2023-11-10-012641.png" style="width: 600px; height: 233px;padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> nums = [7,7,7,7,7,7], k = 3, edges = [[0,1],[0,2],[0,3],[0,4],[0,5]] <strong>Output:</strong> 42 <strong>Explanation:</strong> The maximum achievable sum is 42 which can be achieved by Alice performing no operations. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 2 * 10<sup>4</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= edges[i][0], edges[i][1] &lt;= n - 1</code></li> <li>The input is generated such that <code>edges</code> represent&nbsp;a valid tree.</li> </ul>
Greedy; Bit Manipulation; Tree; Array; Dynamic Programming; Sorting
TypeScript
function maximumValueSum(nums: number[], k: number, edges: number[][]): number { let [f0, f1] = [0, -Infinity]; for (const x of nums) { [f0, f1] = [Math.max(f0 + x, f1 + (x ^ k)), Math.max(f1 + x, f0 + (x ^ k))]; } return f0; }
3,069
Distribute Elements Into Two Arrays I
Easy
<p>You are given a <strong>1-indexed</strong> array of <strong>distinct</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If the last element of <code>arr1</code> is<strong> greater</strong> than the last element of <code>arr2</code>, append <code>nums[i]</code> to <code>arr1</code>. Otherwise, append <code>nums[i]</code> to <code>arr2</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3] <strong>Output:</strong> [2,3,1] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (2 &gt; 1), append nums[3] to arr1. After 3 operations, arr1 = [2,3] and arr2 = [1]. Hence, the array result formed by concatenation is [2,3,1]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,4,3,8] <strong>Output:</strong> [5,3,4,8] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [4]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (5 &gt; 4), append nums[3] to arr1, hence arr1 becomes [5,3]. In the 4<sup>th</sup> operation, as the last element of arr2 is greater than the last element of arr1 (4 &gt; 3), append nums[4] to arr2, hence arr2 becomes [4,8]. After 4 operations, arr1 = [5,3] and arr2 = [4,8]. Hence, the array result formed by concatenation is [5,3,4,8]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li>All elements in <code>nums</code> are distinct.</li> </ul>
Array; Simulation
C++
class Solution { public: vector<int> resultArray(vector<int>& nums) { int n = nums.size(); vector<int> arr1 = {nums[0]}; vector<int> arr2 = {nums[1]}; for (int k = 2; k < n; ++k) { if (arr1.back() > arr2.back()) { arr1.push_back(nums[k]); } else { arr2.push_back(nums[k]); } } arr1.insert(arr1.end(), arr2.begin(), arr2.end()); return arr1; } };
3,069
Distribute Elements Into Two Arrays I
Easy
<p>You are given a <strong>1-indexed</strong> array of <strong>distinct</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If the last element of <code>arr1</code> is<strong> greater</strong> than the last element of <code>arr2</code>, append <code>nums[i]</code> to <code>arr1</code>. Otherwise, append <code>nums[i]</code> to <code>arr2</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3] <strong>Output:</strong> [2,3,1] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (2 &gt; 1), append nums[3] to arr1. After 3 operations, arr1 = [2,3] and arr2 = [1]. Hence, the array result formed by concatenation is [2,3,1]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,4,3,8] <strong>Output:</strong> [5,3,4,8] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [4]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (5 &gt; 4), append nums[3] to arr1, hence arr1 becomes [5,3]. In the 4<sup>th</sup> operation, as the last element of arr2 is greater than the last element of arr1 (4 &gt; 3), append nums[4] to arr2, hence arr2 becomes [4,8]. After 4 operations, arr1 = [5,3] and arr2 = [4,8]. Hence, the array result formed by concatenation is [5,3,4,8]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li>All elements in <code>nums</code> are distinct.</li> </ul>
Array; Simulation
Go
func resultArray(nums []int) []int { arr1 := []int{nums[0]} arr2 := []int{nums[1]} for _, x := range nums[2:] { if arr1[len(arr1)-1] > arr2[len(arr2)-1] { arr1 = append(arr1, x) } else { arr2 = append(arr2, x) } } return append(arr1, arr2...) }
3,069
Distribute Elements Into Two Arrays I
Easy
<p>You are given a <strong>1-indexed</strong> array of <strong>distinct</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If the last element of <code>arr1</code> is<strong> greater</strong> than the last element of <code>arr2</code>, append <code>nums[i]</code> to <code>arr1</code>. Otherwise, append <code>nums[i]</code> to <code>arr2</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3] <strong>Output:</strong> [2,3,1] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (2 &gt; 1), append nums[3] to arr1. After 3 operations, arr1 = [2,3] and arr2 = [1]. Hence, the array result formed by concatenation is [2,3,1]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,4,3,8] <strong>Output:</strong> [5,3,4,8] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [4]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (5 &gt; 4), append nums[3] to arr1, hence arr1 becomes [5,3]. In the 4<sup>th</sup> operation, as the last element of arr2 is greater than the last element of arr1 (4 &gt; 3), append nums[4] to arr2, hence arr2 becomes [4,8]. After 4 operations, arr1 = [5,3] and arr2 = [4,8]. Hence, the array result formed by concatenation is [5,3,4,8]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li>All elements in <code>nums</code> are distinct.</li> </ul>
Array; Simulation
Java
class Solution { public int[] resultArray(int[] nums) { int n = nums.length; int[] arr1 = new int[n]; int[] arr2 = new int[n]; arr1[0] = nums[0]; arr2[0] = nums[1]; int i = 0, j = 0; for (int k = 2; k < n; ++k) { if (arr1[i] > arr2[j]) { arr1[++i] = nums[k]; } else { arr2[++j] = nums[k]; } } for (int k = 0; k <= j; ++k) { arr1[++i] = arr2[k]; } return arr1; } }
3,069
Distribute Elements Into Two Arrays I
Easy
<p>You are given a <strong>1-indexed</strong> array of <strong>distinct</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If the last element of <code>arr1</code> is<strong> greater</strong> than the last element of <code>arr2</code>, append <code>nums[i]</code> to <code>arr1</code>. Otherwise, append <code>nums[i]</code> to <code>arr2</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3] <strong>Output:</strong> [2,3,1] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (2 &gt; 1), append nums[3] to arr1. After 3 operations, arr1 = [2,3] and arr2 = [1]. Hence, the array result formed by concatenation is [2,3,1]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,4,3,8] <strong>Output:</strong> [5,3,4,8] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [4]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (5 &gt; 4), append nums[3] to arr1, hence arr1 becomes [5,3]. In the 4<sup>th</sup> operation, as the last element of arr2 is greater than the last element of arr1 (4 &gt; 3), append nums[4] to arr2, hence arr2 becomes [4,8]. After 4 operations, arr1 = [5,3] and arr2 = [4,8]. Hence, the array result formed by concatenation is [5,3,4,8]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li>All elements in <code>nums</code> are distinct.</li> </ul>
Array; Simulation
Python
class Solution: def resultArray(self, nums: List[int]) -> List[int]: arr1 = [nums[0]] arr2 = [nums[1]] for x in nums[2:]: if arr1[-1] > arr2[-1]: arr1.append(x) else: arr2.append(x) return arr1 + arr2
3,069
Distribute Elements Into Two Arrays I
Easy
<p>You are given a <strong>1-indexed</strong> array of <strong>distinct</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If the last element of <code>arr1</code> is<strong> greater</strong> than the last element of <code>arr2</code>, append <code>nums[i]</code> to <code>arr1</code>. Otherwise, append <code>nums[i]</code> to <code>arr2</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3] <strong>Output:</strong> [2,3,1] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (2 &gt; 1), append nums[3] to arr1. After 3 operations, arr1 = [2,3] and arr2 = [1]. Hence, the array result formed by concatenation is [2,3,1]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,4,3,8] <strong>Output:</strong> [5,3,4,8] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [4]. In the 3<sup>rd</sup> operation, as the last element of arr1 is greater than the last element of arr2 (5 &gt; 4), append nums[3] to arr1, hence arr1 becomes [5,3]. In the 4<sup>th</sup> operation, as the last element of arr2 is greater than the last element of arr1 (4 &gt; 3), append nums[4] to arr2, hence arr2 becomes [4,8]. After 4 operations, arr1 = [5,3] and arr2 = [4,8]. Hence, the array result formed by concatenation is [5,3,4,8]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 50</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li>All elements in <code>nums</code> are distinct.</li> </ul>
Array; Simulation
TypeScript
function resultArray(nums: number[]): number[] { const arr1: number[] = [nums[0]]; const arr2: number[] = [nums[1]]; for (const x of nums.slice(2)) { if (arr1.at(-1)! > arr2.at(-1)!) { arr1.push(x); } else { arr2.push(x); } } return arr1.concat(arr2); }
3,070
Count Submatrices with Top-Left Element and Sum Less Than k
Medium
<p>You are given a <strong>0-indexed</strong> integer matrix <code>grid</code> and an integer <code>k</code>.</p> <p>Return <em>the <strong>number</strong> of <span data-keyword="submatrix">submatrices</span> that contain the top-left element of the</em> <code>grid</code>, <em>and have a sum less than or equal to </em><code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example1.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,6,3],[6,6,1]], k = 18 <strong>Output:</strong> 4 <strong>Explanation:</strong> There are only 4 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 18.</pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example21.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,2,9],[1,5,0],[2,6,6]], k = 20 <strong>Output:</strong> 6 <strong>Explanation:</strong> There are only 6 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 20. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length </code></li> <li><code>n == grid[i].length</code></li> <li><code>1 &lt;= n, m &lt;= 1000 </code></li> <li><code>0 &lt;= grid[i][j] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Array; Matrix; Prefix Sum
C++
class Solution { public: int countSubmatrices(vector<vector<int>>& grid, int k) { int m = grid.size(), n = grid[0].size(); int s[m + 1][n + 1]; memset(s, 0, sizeof(s)); int ans = 0; for (int i = 1; i <= m; ++i) { for (int j = 1; j <= n; ++j) { s[i][j] = s[i - 1][j] + s[i][j - 1] - s[i - 1][j - 1] + grid[i - 1][j - 1]; if (s[i][j] <= k) { ++ans; } } } return ans; } };
3,070
Count Submatrices with Top-Left Element and Sum Less Than k
Medium
<p>You are given a <strong>0-indexed</strong> integer matrix <code>grid</code> and an integer <code>k</code>.</p> <p>Return <em>the <strong>number</strong> of <span data-keyword="submatrix">submatrices</span> that contain the top-left element of the</em> <code>grid</code>, <em>and have a sum less than or equal to </em><code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example1.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,6,3],[6,6,1]], k = 18 <strong>Output:</strong> 4 <strong>Explanation:</strong> There are only 4 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 18.</pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example21.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,2,9],[1,5,0],[2,6,6]], k = 20 <strong>Output:</strong> 6 <strong>Explanation:</strong> There are only 6 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 20. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length </code></li> <li><code>n == grid[i].length</code></li> <li><code>1 &lt;= n, m &lt;= 1000 </code></li> <li><code>0 &lt;= grid[i][j] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Array; Matrix; Prefix Sum
Go
func countSubmatrices(grid [][]int, k int) (ans int) { s := make([][]int, len(grid)+1) for i := range s { s[i] = make([]int, len(grid[0])+1) } for i, row := range grid { for j, x := range row { s[i+1][j+1] = s[i+1][j] + s[i][j+1] - s[i][j] + x if s[i+1][j+1] <= k { ans++ } } } return }
3,070
Count Submatrices with Top-Left Element and Sum Less Than k
Medium
<p>You are given a <strong>0-indexed</strong> integer matrix <code>grid</code> and an integer <code>k</code>.</p> <p>Return <em>the <strong>number</strong> of <span data-keyword="submatrix">submatrices</span> that contain the top-left element of the</em> <code>grid</code>, <em>and have a sum less than or equal to </em><code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example1.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,6,3],[6,6,1]], k = 18 <strong>Output:</strong> 4 <strong>Explanation:</strong> There are only 4 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 18.</pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example21.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,2,9],[1,5,0],[2,6,6]], k = 20 <strong>Output:</strong> 6 <strong>Explanation:</strong> There are only 6 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 20. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length </code></li> <li><code>n == grid[i].length</code></li> <li><code>1 &lt;= n, m &lt;= 1000 </code></li> <li><code>0 &lt;= grid[i][j] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Array; Matrix; Prefix Sum
Java
class Solution { public int countSubmatrices(int[][] grid, int k) { int m = grid.length, n = grid[0].length; int[][] s = new int[m + 1][n + 1]; int ans = 0; for (int i = 1; i <= m; ++i) { for (int j = 1; j <= n; ++j) { s[i][j] = s[i - 1][j] + s[i][j - 1] - s[i - 1][j - 1] + grid[i - 1][j - 1]; if (s[i][j] <= k) { ++ans; } } } return ans; } }
3,070
Count Submatrices with Top-Left Element and Sum Less Than k
Medium
<p>You are given a <strong>0-indexed</strong> integer matrix <code>grid</code> and an integer <code>k</code>.</p> <p>Return <em>the <strong>number</strong> of <span data-keyword="submatrix">submatrices</span> that contain the top-left element of the</em> <code>grid</code>, <em>and have a sum less than or equal to </em><code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example1.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,6,3],[6,6,1]], k = 18 <strong>Output:</strong> 4 <strong>Explanation:</strong> There are only 4 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 18.</pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example21.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,2,9],[1,5,0],[2,6,6]], k = 20 <strong>Output:</strong> 6 <strong>Explanation:</strong> There are only 6 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 20. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length </code></li> <li><code>n == grid[i].length</code></li> <li><code>1 &lt;= n, m &lt;= 1000 </code></li> <li><code>0 &lt;= grid[i][j] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Array; Matrix; Prefix Sum
Python
class Solution: def countSubmatrices(self, grid: List[List[int]], k: int) -> int: s = [[0] * (len(grid[0]) + 1) for _ in range(len(grid) + 1)] ans = 0 for i, row in enumerate(grid, 1): for j, x in enumerate(row, 1): s[i][j] = s[i - 1][j] + s[i][j - 1] - s[i - 1][j - 1] + x ans += s[i][j] <= k return ans
3,070
Count Submatrices with Top-Left Element and Sum Less Than k
Medium
<p>You are given a <strong>0-indexed</strong> integer matrix <code>grid</code> and an integer <code>k</code>.</p> <p>Return <em>the <strong>number</strong> of <span data-keyword="submatrix">submatrices</span> that contain the top-left element of the</em> <code>grid</code>, <em>and have a sum less than or equal to </em><code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example1.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,6,3],[6,6,1]], k = 18 <strong>Output:</strong> 4 <strong>Explanation:</strong> There are only 4 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 18.</pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3070.Count%20Submatrices%20with%20Top-Left%20Element%20and%20Sum%20Less%20Than%20k/images/example21.png" style="padding: 10px; background: #fff; border-radius: .5rem;" /> <pre> <strong>Input:</strong> grid = [[7,2,9],[1,5,0],[2,6,6]], k = 20 <strong>Output:</strong> 6 <strong>Explanation:</strong> There are only 6 submatrices, shown in the image above, that contain the top-left element of grid, and have a sum less than or equal to 20. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length </code></li> <li><code>n == grid[i].length</code></li> <li><code>1 &lt;= n, m &lt;= 1000 </code></li> <li><code>0 &lt;= grid[i][j] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Array; Matrix; Prefix Sum
TypeScript
function countSubmatrices(grid: number[][], k: number): number { const m = grid.length; const n = grid[0].length; const s: number[][] = Array.from({ length: m + 1 }, () => Array(n + 1).fill(0)); let ans: number = 0; for (let i = 1; i <= m; ++i) { for (let j = 1; j <= n; ++j) { s[i][j] = s[i - 1][j] + s[i][j - 1] - s[i - 1][j - 1] + grid[i - 1][j - 1]; if (s[i][j] <= k) { ++ans; } } } return ans; }
3,071
Minimum Operations to Write the Letter Y on a Grid
Medium
<p>You are given a <strong>0-indexed</strong> <code>n x n</code> grid where <code>n</code> is odd, and <code>grid[r][c]</code> is <code>0</code>, <code>1</code>, or <code>2</code>.</p> <p>We say that a cell belongs to the Letter <strong>Y</strong> if it belongs to one of the following:</p> <ul> <li>The diagonal starting at the top-left cell and ending at the center cell of the grid.</li> <li>The diagonal starting at the top-right cell and ending at the center cell of the grid.</li> <li>The vertical line starting at the center cell and ending at the bottom border of the grid.</li> </ul> <p>The Letter <strong>Y</strong> is written on the grid if and only if:</p> <ul> <li>All values at cells belonging to the Y are equal.</li> <li>All values at cells not belonging to the Y are equal.</li> <li>The values at cells belonging to the Y are different from the values at cells not belonging to the Y.</li> </ul> <p>Return <em>the <strong>minimum</strong> number of operations needed to write the letter Y on the grid given that in one operation you can change the value at any cell to</em> <code>0</code><em>,</em> <code>1</code><em>,</em> <em>or</em> <code>2</code><em>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y2.png" style="width: 461px; height: 121px;" /> <pre> <strong>Input:</strong> grid = [[1,2,2],[1,1,0],[0,1,0]] <strong>Output:</strong> 3 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 1 while those that do not belong to Y are equal to 0. It can be shown that 3 is the minimum number of operations needed to write Y on the grid. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y3.png" style="width: 701px; height: 201px;" /> <pre> <strong>Input:</strong> grid = [[0,1,0,1,0],[2,1,0,1,2],[2,2,2,0,1],[2,2,2,2,2],[2,1,2,2,2]] <strong>Output:</strong> 12 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 0 while those that do not belong to Y are equal to 2. It can be shown that 12 is the minimum number of operations needed to write Y on the grid.</pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 49 </code></li> <li><code>n == grid.length == grid[i].length</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 2</code></li> <li><code>n</code> is odd.</li> </ul>
Array; Hash Table; Counting; Matrix
C++
class Solution { public: int minimumOperationsToWriteY(vector<vector<int>>& grid) { int n = grid.size(); int cnt1[3]{}; int cnt2[3]{}; for (int i = 0; i < n; ++i) { for (int j = 0; j < n; ++j) { bool a = i == j && i <= n / 2; bool b = i + j == n - 1 && i <= n / 2; bool c = j == n / 2 && i >= n / 2; if (a || b || c) { ++cnt1[grid[i][j]]; } else { ++cnt2[grid[i][j]]; } } } int ans = n * n; for (int i = 0; i < 3; ++i) { for (int j = 0; j < 3; ++j) { if (i != j) { ans = min(ans, n * n - cnt1[i] - cnt2[j]); } } } return ans; } };
3,071
Minimum Operations to Write the Letter Y on a Grid
Medium
<p>You are given a <strong>0-indexed</strong> <code>n x n</code> grid where <code>n</code> is odd, and <code>grid[r][c]</code> is <code>0</code>, <code>1</code>, or <code>2</code>.</p> <p>We say that a cell belongs to the Letter <strong>Y</strong> if it belongs to one of the following:</p> <ul> <li>The diagonal starting at the top-left cell and ending at the center cell of the grid.</li> <li>The diagonal starting at the top-right cell and ending at the center cell of the grid.</li> <li>The vertical line starting at the center cell and ending at the bottom border of the grid.</li> </ul> <p>The Letter <strong>Y</strong> is written on the grid if and only if:</p> <ul> <li>All values at cells belonging to the Y are equal.</li> <li>All values at cells not belonging to the Y are equal.</li> <li>The values at cells belonging to the Y are different from the values at cells not belonging to the Y.</li> </ul> <p>Return <em>the <strong>minimum</strong> number of operations needed to write the letter Y on the grid given that in one operation you can change the value at any cell to</em> <code>0</code><em>,</em> <code>1</code><em>,</em> <em>or</em> <code>2</code><em>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y2.png" style="width: 461px; height: 121px;" /> <pre> <strong>Input:</strong> grid = [[1,2,2],[1,1,0],[0,1,0]] <strong>Output:</strong> 3 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 1 while those that do not belong to Y are equal to 0. It can be shown that 3 is the minimum number of operations needed to write Y on the grid. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y3.png" style="width: 701px; height: 201px;" /> <pre> <strong>Input:</strong> grid = [[0,1,0,1,0],[2,1,0,1,2],[2,2,2,0,1],[2,2,2,2,2],[2,1,2,2,2]] <strong>Output:</strong> 12 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 0 while those that do not belong to Y are equal to 2. It can be shown that 12 is the minimum number of operations needed to write Y on the grid.</pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 49 </code></li> <li><code>n == grid.length == grid[i].length</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 2</code></li> <li><code>n</code> is odd.</li> </ul>
Array; Hash Table; Counting; Matrix
Go
func minimumOperationsToWriteY(grid [][]int) int { n := len(grid) cnt1 := [3]int{} cnt2 := [3]int{} for i, row := range grid { for j, x := range row { a := i == j && i <= n/2 b := i+j == n-1 && i <= n/2 c := j == n/2 && i >= n/2 if a || b || c { cnt1[x]++ } else { cnt2[x]++ } } } ans := n * n for i := 0; i < 3; i++ { for j := 0; j < 3; j++ { if i != j { ans = min(ans, n*n-cnt1[i]-cnt2[j]) } } } return ans }
3,071
Minimum Operations to Write the Letter Y on a Grid
Medium
<p>You are given a <strong>0-indexed</strong> <code>n x n</code> grid where <code>n</code> is odd, and <code>grid[r][c]</code> is <code>0</code>, <code>1</code>, or <code>2</code>.</p> <p>We say that a cell belongs to the Letter <strong>Y</strong> if it belongs to one of the following:</p> <ul> <li>The diagonal starting at the top-left cell and ending at the center cell of the grid.</li> <li>The diagonal starting at the top-right cell and ending at the center cell of the grid.</li> <li>The vertical line starting at the center cell and ending at the bottom border of the grid.</li> </ul> <p>The Letter <strong>Y</strong> is written on the grid if and only if:</p> <ul> <li>All values at cells belonging to the Y are equal.</li> <li>All values at cells not belonging to the Y are equal.</li> <li>The values at cells belonging to the Y are different from the values at cells not belonging to the Y.</li> </ul> <p>Return <em>the <strong>minimum</strong> number of operations needed to write the letter Y on the grid given that in one operation you can change the value at any cell to</em> <code>0</code><em>,</em> <code>1</code><em>,</em> <em>or</em> <code>2</code><em>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y2.png" style="width: 461px; height: 121px;" /> <pre> <strong>Input:</strong> grid = [[1,2,2],[1,1,0],[0,1,0]] <strong>Output:</strong> 3 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 1 while those that do not belong to Y are equal to 0. It can be shown that 3 is the minimum number of operations needed to write Y on the grid. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y3.png" style="width: 701px; height: 201px;" /> <pre> <strong>Input:</strong> grid = [[0,1,0,1,0],[2,1,0,1,2],[2,2,2,0,1],[2,2,2,2,2],[2,1,2,2,2]] <strong>Output:</strong> 12 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 0 while those that do not belong to Y are equal to 2. It can be shown that 12 is the minimum number of operations needed to write Y on the grid.</pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 49 </code></li> <li><code>n == grid.length == grid[i].length</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 2</code></li> <li><code>n</code> is odd.</li> </ul>
Array; Hash Table; Counting; Matrix
Java
class Solution { public int minimumOperationsToWriteY(int[][] grid) { int n = grid.length; int[] cnt1 = new int[3]; int[] cnt2 = new int[3]; for (int i = 0; i < n; ++i) { for (int j = 0; j < n; ++j) { boolean a = i == j && i <= n / 2; boolean b = i + j == n - 1 && i <= n / 2; boolean c = j == n / 2 && i >= n / 2; if (a || b || c) { ++cnt1[grid[i][j]]; } else { ++cnt2[grid[i][j]]; } } } int ans = n * n; for (int i = 0; i < 3; ++i) { for (int j = 0; j < 3; ++j) { if (i != j) { ans = Math.min(ans, n * n - cnt1[i] - cnt2[j]); } } } return ans; } }
3,071
Minimum Operations to Write the Letter Y on a Grid
Medium
<p>You are given a <strong>0-indexed</strong> <code>n x n</code> grid where <code>n</code> is odd, and <code>grid[r][c]</code> is <code>0</code>, <code>1</code>, or <code>2</code>.</p> <p>We say that a cell belongs to the Letter <strong>Y</strong> if it belongs to one of the following:</p> <ul> <li>The diagonal starting at the top-left cell and ending at the center cell of the grid.</li> <li>The diagonal starting at the top-right cell and ending at the center cell of the grid.</li> <li>The vertical line starting at the center cell and ending at the bottom border of the grid.</li> </ul> <p>The Letter <strong>Y</strong> is written on the grid if and only if:</p> <ul> <li>All values at cells belonging to the Y are equal.</li> <li>All values at cells not belonging to the Y are equal.</li> <li>The values at cells belonging to the Y are different from the values at cells not belonging to the Y.</li> </ul> <p>Return <em>the <strong>minimum</strong> number of operations needed to write the letter Y on the grid given that in one operation you can change the value at any cell to</em> <code>0</code><em>,</em> <code>1</code><em>,</em> <em>or</em> <code>2</code><em>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y2.png" style="width: 461px; height: 121px;" /> <pre> <strong>Input:</strong> grid = [[1,2,2],[1,1,0],[0,1,0]] <strong>Output:</strong> 3 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 1 while those that do not belong to Y are equal to 0. It can be shown that 3 is the minimum number of operations needed to write Y on the grid. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y3.png" style="width: 701px; height: 201px;" /> <pre> <strong>Input:</strong> grid = [[0,1,0,1,0],[2,1,0,1,2],[2,2,2,0,1],[2,2,2,2,2],[2,1,2,2,2]] <strong>Output:</strong> 12 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 0 while those that do not belong to Y are equal to 2. It can be shown that 12 is the minimum number of operations needed to write Y on the grid.</pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 49 </code></li> <li><code>n == grid.length == grid[i].length</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 2</code></li> <li><code>n</code> is odd.</li> </ul>
Array; Hash Table; Counting; Matrix
Python
class Solution: def minimumOperationsToWriteY(self, grid: List[List[int]]) -> int: n = len(grid) cnt1 = Counter() cnt2 = Counter() for i, row in enumerate(grid): for j, x in enumerate(row): a = i == j and i <= n // 2 b = i + j == n - 1 and i <= n // 2 c = j == n // 2 and i >= n // 2 if a or b or c: cnt1[x] += 1 else: cnt2[x] += 1 return min( n * n - cnt1[i] - cnt2[j] for i in range(3) for j in range(3) if i != j )
3,071
Minimum Operations to Write the Letter Y on a Grid
Medium
<p>You are given a <strong>0-indexed</strong> <code>n x n</code> grid where <code>n</code> is odd, and <code>grid[r][c]</code> is <code>0</code>, <code>1</code>, or <code>2</code>.</p> <p>We say that a cell belongs to the Letter <strong>Y</strong> if it belongs to one of the following:</p> <ul> <li>The diagonal starting at the top-left cell and ending at the center cell of the grid.</li> <li>The diagonal starting at the top-right cell and ending at the center cell of the grid.</li> <li>The vertical line starting at the center cell and ending at the bottom border of the grid.</li> </ul> <p>The Letter <strong>Y</strong> is written on the grid if and only if:</p> <ul> <li>All values at cells belonging to the Y are equal.</li> <li>All values at cells not belonging to the Y are equal.</li> <li>The values at cells belonging to the Y are different from the values at cells not belonging to the Y.</li> </ul> <p>Return <em>the <strong>minimum</strong> number of operations needed to write the letter Y on the grid given that in one operation you can change the value at any cell to</em> <code>0</code><em>,</em> <code>1</code><em>,</em> <em>or</em> <code>2</code><em>.</em></p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y2.png" style="width: 461px; height: 121px;" /> <pre> <strong>Input:</strong> grid = [[1,2,2],[1,1,0],[0,1,0]] <strong>Output:</strong> 3 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 1 while those that do not belong to Y are equal to 0. It can be shown that 3 is the minimum number of operations needed to write Y on the grid. </pre> <p><strong class="example">Example 2:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3000-3099/3071.Minimum%20Operations%20to%20Write%20the%20Letter%20Y%20on%20a%20Grid/images/y3.png" style="width: 701px; height: 201px;" /> <pre> <strong>Input:</strong> grid = [[0,1,0,1,0],[2,1,0,1,2],[2,2,2,0,1],[2,2,2,2,2],[2,1,2,2,2]] <strong>Output:</strong> 12 <strong>Explanation:</strong> We can write Y on the grid by applying the changes highlighted in blue in the image above. After the operations, all cells that belong to Y, denoted in bold, have the same value of 0 while those that do not belong to Y are equal to 2. It can be shown that 12 is the minimum number of operations needed to write Y on the grid.</pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 49 </code></li> <li><code>n == grid.length == grid[i].length</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 2</code></li> <li><code>n</code> is odd.</li> </ul>
Array; Hash Table; Counting; Matrix
TypeScript
function minimumOperationsToWriteY(grid: number[][]): number { const n = grid.length; const cnt1: number[] = Array(3).fill(0); const cnt2: number[] = Array(3).fill(0); for (let i = 0; i < n; ++i) { for (let j = 0; j < n; ++j) { const a = i === j && i <= n >> 1; const b = i + j === n - 1 && i <= n >> 1; const c = j === n >> 1 && i >= n >> 1; if (a || b || c) { ++cnt1[grid[i][j]]; } else { ++cnt2[grid[i][j]]; } } } let ans = n * n; for (let i = 0; i < 3; ++i) { for (let j = 0; j < 3; ++j) { if (i !== j) { ans = Math.min(ans, n * n - cnt1[i] - cnt2[j]); } } } return ans; }
3,072
Distribute Elements Into Two Arrays II
Hard
<p>You are given a <strong>1-indexed</strong> array of integers <code>nums</code> of length <code>n</code>.</p> <p>We define a function <code>greaterCount</code> such that <code>greaterCount(arr, val)</code> returns the number of elements in <code>arr</code> that are <strong>strictly greater</strong> than <code>val</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If <code>greaterCount(arr1, nums[i]) &gt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr1</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) &lt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr2</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) == greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to the array with a <strong>lesser</strong> number of elements.</li> <li>If there is still a tie, append <code>nums[i]</code> to <code>arr1</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the integer array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3,3] <strong>Output:</strong> [2,3,1,3] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is zero in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 3 is zero in both arrays. As the length of arr2 is lesser, hence, append nums[4] to arr2. After 4 operations, arr1 = [2,3] and arr2 = [1,3]. Hence, the array result formed by concatenation is [2,3,1,3]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,14,3,1,2] <strong>Output:</strong> [5,3,1,2,14] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [14]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is one in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 1 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[4] to arr1. In the 5<sup>th</sup> operation, the number of elements greater than 2 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[5] to arr1. After 5 operations, arr1 = [5,3,1,2] and arr2 = [14]. Hence, the array result formed by concatenation is [5,3,1,2,14]. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [3,3,3,3] <strong>Output:</strong> [3,3,3,3] <strong>Explanation:</strong> At the end of 4 operations, arr1 = [3,3] and arr2 = [3,3]. Hence, the array result formed by concatenation is [3,3,3,3]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> </ul>
Binary Indexed Tree; Segment Tree; Array; Simulation
C++
class BinaryIndexedTree { private: int n; vector<int> c; public: BinaryIndexedTree(int n) : n(n) , c(n + 1) {} void update(int x, int delta) { for (; x <= n; x += x & -x) { c[x] += delta; } } int query(int x) { int s = 0; for (; x > 0; x -= x & -x) { s += c[x]; } return s; } }; class Solution { public: vector<int> resultArray(vector<int>& nums) { vector<int> st = nums; sort(st.begin(), st.end()); int n = st.size(); BinaryIndexedTree tree1(n + 1); BinaryIndexedTree tree2(n + 1); tree1.update(distance(st.begin(), lower_bound(st.begin(), st.end(), nums[0])) + 1, 1); tree2.update(distance(st.begin(), lower_bound(st.begin(), st.end(), nums[1])) + 1, 1); vector<int> arr1 = {nums[0]}; vector<int> arr2 = {nums[1]}; for (int k = 2; k < n; ++k) { int x = distance(st.begin(), lower_bound(st.begin(), st.end(), nums[k])) + 1; int a = arr1.size() - tree1.query(x); int b = arr2.size() - tree2.query(x); if (a > b) { arr1.push_back(nums[k]); tree1.update(x, 1); } else if (a < b) { arr2.push_back(nums[k]); tree2.update(x, 1); } else if (arr1.size() <= arr2.size()) { arr1.push_back(nums[k]); tree1.update(x, 1); } else { arr2.push_back(nums[k]); tree2.update(x, 1); } } arr1.insert(arr1.end(), arr2.begin(), arr2.end()); return arr1; } };
3,072
Distribute Elements Into Two Arrays II
Hard
<p>You are given a <strong>1-indexed</strong> array of integers <code>nums</code> of length <code>n</code>.</p> <p>We define a function <code>greaterCount</code> such that <code>greaterCount(arr, val)</code> returns the number of elements in <code>arr</code> that are <strong>strictly greater</strong> than <code>val</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If <code>greaterCount(arr1, nums[i]) &gt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr1</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) &lt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr2</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) == greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to the array with a <strong>lesser</strong> number of elements.</li> <li>If there is still a tie, append <code>nums[i]</code> to <code>arr1</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the integer array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3,3] <strong>Output:</strong> [2,3,1,3] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is zero in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 3 is zero in both arrays. As the length of arr2 is lesser, hence, append nums[4] to arr2. After 4 operations, arr1 = [2,3] and arr2 = [1,3]. Hence, the array result formed by concatenation is [2,3,1,3]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,14,3,1,2] <strong>Output:</strong> [5,3,1,2,14] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [14]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is one in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 1 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[4] to arr1. In the 5<sup>th</sup> operation, the number of elements greater than 2 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[5] to arr1. After 5 operations, arr1 = [5,3,1,2] and arr2 = [14]. Hence, the array result formed by concatenation is [5,3,1,2,14]. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [3,3,3,3] <strong>Output:</strong> [3,3,3,3] <strong>Explanation:</strong> At the end of 4 operations, arr1 = [3,3] and arr2 = [3,3]. Hence, the array result formed by concatenation is [3,3,3,3]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> </ul>
Binary Indexed Tree; Segment Tree; Array; Simulation
Go
type BinaryIndexedTree struct { n int c []int } func NewBinaryIndexedTree(n int) *BinaryIndexedTree { return &BinaryIndexedTree{n: n, c: make([]int, n+1)} } func (bit *BinaryIndexedTree) update(x, delta int) { for ; x <= bit.n; x += x & -x { bit.c[x] += delta } } func (bit *BinaryIndexedTree) query(x int) int { s := 0 for ; x > 0; x -= x & -x { s += bit.c[x] } return s } func resultArray(nums []int) []int { st := make([]int, len(nums)) copy(st, nums) sort.Ints(st) n := len(st) tree1 := NewBinaryIndexedTree(n + 1) tree2 := NewBinaryIndexedTree(n + 1) tree1.update(sort.SearchInts(st, nums[0])+1, 1) tree2.update(sort.SearchInts(st, nums[1])+1, 1) arr1 := []int{nums[0]} arr2 := []int{nums[1]} for _, x := range nums[2:] { i := sort.SearchInts(st, x) + 1 a := len(arr1) - tree1.query(i) b := len(arr2) - tree2.query(i) if a > b { arr1 = append(arr1, x) tree1.update(i, 1) } else if a < b { arr2 = append(arr2, x) tree2.update(i, 1) } else if len(arr1) <= len(arr2) { arr1 = append(arr1, x) tree1.update(i, 1) } else { arr2 = append(arr2, x) tree2.update(i, 1) } } arr1 = append(arr1, arr2...) return arr1 }
3,072
Distribute Elements Into Two Arrays II
Hard
<p>You are given a <strong>1-indexed</strong> array of integers <code>nums</code> of length <code>n</code>.</p> <p>We define a function <code>greaterCount</code> such that <code>greaterCount(arr, val)</code> returns the number of elements in <code>arr</code> that are <strong>strictly greater</strong> than <code>val</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If <code>greaterCount(arr1, nums[i]) &gt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr1</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) &lt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr2</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) == greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to the array with a <strong>lesser</strong> number of elements.</li> <li>If there is still a tie, append <code>nums[i]</code> to <code>arr1</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the integer array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3,3] <strong>Output:</strong> [2,3,1,3] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is zero in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 3 is zero in both arrays. As the length of arr2 is lesser, hence, append nums[4] to arr2. After 4 operations, arr1 = [2,3] and arr2 = [1,3]. Hence, the array result formed by concatenation is [2,3,1,3]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,14,3,1,2] <strong>Output:</strong> [5,3,1,2,14] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [14]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is one in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 1 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[4] to arr1. In the 5<sup>th</sup> operation, the number of elements greater than 2 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[5] to arr1. After 5 operations, arr1 = [5,3,1,2] and arr2 = [14]. Hence, the array result formed by concatenation is [5,3,1,2,14]. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [3,3,3,3] <strong>Output:</strong> [3,3,3,3] <strong>Explanation:</strong> At the end of 4 operations, arr1 = [3,3] and arr2 = [3,3]. Hence, the array result formed by concatenation is [3,3,3,3]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> </ul>
Binary Indexed Tree; Segment Tree; Array; Simulation
Java
class BinaryIndexedTree { private int n; private int[] c; public BinaryIndexedTree(int n) { this.n = n; this.c = new int[n + 1]; } public void update(int x, int delta) { for (; x <= n; x += x & -x) { c[x] += delta; } } public int query(int x) { int s = 0; for (; x > 0; x -= x & -x) { s += c[x]; } return s; } } class Solution { public int[] resultArray(int[] nums) { int[] st = nums.clone(); Arrays.sort(st); int n = st.length; BinaryIndexedTree tree1 = new BinaryIndexedTree(n + 1); BinaryIndexedTree tree2 = new BinaryIndexedTree(n + 1); tree1.update(Arrays.binarySearch(st, nums[0]) + 1, 1); tree2.update(Arrays.binarySearch(st, nums[1]) + 1, 1); int[] arr1 = new int[n]; int[] arr2 = new int[n]; arr1[0] = nums[0]; arr2[0] = nums[1]; int i = 1, j = 1; for (int k = 2; k < n; ++k) { int x = Arrays.binarySearch(st, nums[k]) + 1; int a = i - tree1.query(x); int b = j - tree2.query(x); if (a > b) { arr1[i++] = nums[k]; tree1.update(x, 1); } else if (a < b) { arr2[j++] = nums[k]; tree2.update(x, 1); } else if (i <= j) { arr1[i++] = nums[k]; tree1.update(x, 1); } else { arr2[j++] = nums[k]; tree2.update(x, 1); } } for (int k = 0; k < j; ++k) { arr1[i++] = arr2[k]; } return arr1; } }
3,072
Distribute Elements Into Two Arrays II
Hard
<p>You are given a <strong>1-indexed</strong> array of integers <code>nums</code> of length <code>n</code>.</p> <p>We define a function <code>greaterCount</code> such that <code>greaterCount(arr, val)</code> returns the number of elements in <code>arr</code> that are <strong>strictly greater</strong> than <code>val</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If <code>greaterCount(arr1, nums[i]) &gt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr1</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) &lt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr2</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) == greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to the array with a <strong>lesser</strong> number of elements.</li> <li>If there is still a tie, append <code>nums[i]</code> to <code>arr1</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the integer array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3,3] <strong>Output:</strong> [2,3,1,3] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is zero in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 3 is zero in both arrays. As the length of arr2 is lesser, hence, append nums[4] to arr2. After 4 operations, arr1 = [2,3] and arr2 = [1,3]. Hence, the array result formed by concatenation is [2,3,1,3]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,14,3,1,2] <strong>Output:</strong> [5,3,1,2,14] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [14]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is one in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 1 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[4] to arr1. In the 5<sup>th</sup> operation, the number of elements greater than 2 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[5] to arr1. After 5 operations, arr1 = [5,3,1,2] and arr2 = [14]. Hence, the array result formed by concatenation is [5,3,1,2,14]. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [3,3,3,3] <strong>Output:</strong> [3,3,3,3] <strong>Explanation:</strong> At the end of 4 operations, arr1 = [3,3] and arr2 = [3,3]. Hence, the array result formed by concatenation is [3,3,3,3]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> </ul>
Binary Indexed Tree; Segment Tree; Array; Simulation
Python
class BinaryIndexedTree: __slots__ = "n", "c" def __init__(self, n: int): self.n = n self.c = [0] * (n + 1) def update(self, x: int, delta: int) -> None: while x <= self.n: self.c[x] += delta x += x & -x def query(self, x: int) -> int: s = 0 while x: s += self.c[x] x -= x & -x return s class Solution: def resultArray(self, nums: List[int]) -> List[int]: st = sorted(set(nums)) m = len(st) tree1 = BinaryIndexedTree(m + 1) tree2 = BinaryIndexedTree(m + 1) tree1.update(bisect_left(st, nums[0]) + 1, 1) tree2.update(bisect_left(st, nums[1]) + 1, 1) arr1 = [nums[0]] arr2 = [nums[1]] for x in nums[2:]: i = bisect_left(st, x) + 1 a = len(arr1) - tree1.query(i) b = len(arr2) - tree2.query(i) if a > b: arr1.append(x) tree1.update(i, 1) elif a < b: arr2.append(x) tree2.update(i, 1) elif len(arr1) <= len(arr2): arr1.append(x) tree1.update(i, 1) else: arr2.append(x) tree2.update(i, 1) return arr1 + arr2
3,072
Distribute Elements Into Two Arrays II
Hard
<p>You are given a <strong>1-indexed</strong> array of integers <code>nums</code> of length <code>n</code>.</p> <p>We define a function <code>greaterCount</code> such that <code>greaterCount(arr, val)</code> returns the number of elements in <code>arr</code> that are <strong>strictly greater</strong> than <code>val</code>.</p> <p>You need to distribute all the elements of <code>nums</code> between two arrays <code>arr1</code> and <code>arr2</code> using <code>n</code> operations. In the first operation, append <code>nums[1]</code> to <code>arr1</code>. In the second operation, append <code>nums[2]</code> to <code>arr2</code>. Afterwards, in the <code>i<sup>th</sup></code> operation:</p> <ul> <li>If <code>greaterCount(arr1, nums[i]) &gt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr1</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) &lt; greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to <code>arr2</code>.</li> <li>If <code>greaterCount(arr1, nums[i]) == greaterCount(arr2, nums[i])</code>, append <code>nums[i]</code> to the array with a <strong>lesser</strong> number of elements.</li> <li>If there is still a tie, append <code>nums[i]</code> to <code>arr1</code>.</li> </ul> <p>The array <code>result</code> is formed by concatenating the arrays <code>arr1</code> and <code>arr2</code>. For example, if <code>arr1 == [1,2,3]</code> and <code>arr2 == [4,5,6]</code>, then <code>result = [1,2,3,4,5,6]</code>.</p> <p>Return <em>the integer array</em> <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [2,1,3,3] <strong>Output:</strong> [2,3,1,3] <strong>Explanation:</strong> After the first 2 operations, arr1 = [2] and arr2 = [1]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is zero in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 3 is zero in both arrays. As the length of arr2 is lesser, hence, append nums[4] to arr2. After 4 operations, arr1 = [2,3] and arr2 = [1,3]. Hence, the array result formed by concatenation is [2,3,1,3]. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,14,3,1,2] <strong>Output:</strong> [5,3,1,2,14] <strong>Explanation:</strong> After the first 2 operations, arr1 = [5] and arr2 = [14]. In the 3<sup>rd</sup> operation, the number of elements greater than 3 is one in both arrays. Also, the lengths are equal, hence, append nums[3] to arr1. In the 4<sup>th</sup> operation, the number of elements greater than 1 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[4] to arr1. In the 5<sup>th</sup> operation, the number of elements greater than 2 is greater in arr1 than arr2 (2 &gt; 1). Hence, append nums[5] to arr1. After 5 operations, arr1 = [5,3,1,2] and arr2 = [14]. Hence, the array result formed by concatenation is [5,3,1,2,14]. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> nums = [3,3,3,3] <strong>Output:</strong> [3,3,3,3] <strong>Explanation:</strong> At the end of 4 operations, arr1 = [3,3] and arr2 = [3,3]. Hence, the array result formed by concatenation is [3,3,3,3]. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> </ul>
Binary Indexed Tree; Segment Tree; Array; Simulation
TypeScript
class BinaryIndexedTree { private n: number; private c: number[]; constructor(n: number) { this.n = n; this.c = Array(n + 1).fill(0); } update(x: number, delta: number): void { for (; x <= this.n; x += x & -x) { this.c[x] += delta; } } query(x: number): number { let s = 0; for (; x > 0; x -= x & -x) { s += this.c[x]; } return s; } } function resultArray(nums: number[]): number[] { const st: number[] = nums.slice().sort((a, b) => a - b); const n: number = st.length; const search = (x: number): number => { let [l, r] = [0, n]; while (l < r) { const mid = (l + r) >> 1; if (st[mid] >= x) { r = mid; } else { l = mid + 1; } } return l; }; const tree1: BinaryIndexedTree = new BinaryIndexedTree(n + 1); const tree2: BinaryIndexedTree = new BinaryIndexedTree(n + 1); tree1.update(search(nums[0]) + 1, 1); tree2.update(search(nums[1]) + 1, 1); const arr1: number[] = [nums[0]]; const arr2: number[] = [nums[1]]; for (const x of nums.slice(2)) { const i: number = search(x) + 1; const a: number = arr1.length - tree1.query(i); const b: number = arr2.length - tree2.query(i); if (a > b) { arr1.push(x); tree1.update(i, 1); } else if (a < b) { arr2.push(x); tree2.update(i, 1); } else if (arr1.length <= arr2.length) { arr1.push(x); tree1.update(i, 1); } else { arr2.push(x); tree2.update(i, 1); } } return arr1.concat(arr2); }
3,073
Maximum Increasing Triplet Value
Medium
<p>Given an array <code>nums</code>, return <em>the <strong>maximum value</strong> of a triplet</em> <code>(i, j, k)</code> <em>such that</em> <code>i &lt; j &lt; k</code> <em>and</em> <code>nums[i] &lt; nums[j] &lt; nums[k]</code>.</p> <p>The <strong>value</strong> of a triplet <code>(i, j, k)</code> is <code>nums[i] - nums[j] + nums[k]</code>.</p> <div id="gtx-trans" style="position: absolute; left: 274px; top: 102px;"> <div class="gtx-trans-icon"> </div> </div> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">nums = [5,6,9] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">8 </span></p> <p><strong>Explanation: </strong> We only have one choice for an increasing triplet and that is choosing all three elements. The value of this triplet would be <code>5 - 6 + 9 = 8</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> nums = [1,5,3,6] </span></p> <p><strong>Output:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 4 </span></p> <p><strong>Explanation: </strong> There are only two increasing triplets:</p> <p><code>(0, 1, 3)</code>: The value of this triplet is <code>nums[0] - nums[1] + nums[3] = 1 - 5 + 6 = 2</code>.</p> <p><code>(0, 2, 3)</code>: The value of this triplet is <code>nums[0] - nums[2] + nums[3] = 1 - 3 + 6 = 4</code>.</p> <p>Thus the answer would be <code>4</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that at least one triplet meets the given condition.</li> </ul>
Array; Ordered Set
C++
class Solution { public: int maximumTripletValue(vector<int>& nums) { int n = nums.size(); vector<int> right(n, nums.back()); for (int i = n - 2; ~i; --i) { right[i] = max(nums[i], right[i + 1]); } set<int> ts; ts.insert(nums[0]); int ans = 0; for (int j = 1; j < n - 1; ++j) { if (right[j + 1] > nums[j]) { auto it = ts.lower_bound(nums[j]); if (it != ts.begin()) { --it; ans = max(ans, *it - nums[j] + right[j + 1]); } } ts.insert(nums[j]); } return ans; } };
3,073
Maximum Increasing Triplet Value
Medium
<p>Given an array <code>nums</code>, return <em>the <strong>maximum value</strong> of a triplet</em> <code>(i, j, k)</code> <em>such that</em> <code>i &lt; j &lt; k</code> <em>and</em> <code>nums[i] &lt; nums[j] &lt; nums[k]</code>.</p> <p>The <strong>value</strong> of a triplet <code>(i, j, k)</code> is <code>nums[i] - nums[j] + nums[k]</code>.</p> <div id="gtx-trans" style="position: absolute; left: 274px; top: 102px;"> <div class="gtx-trans-icon"> </div> </div> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">nums = [5,6,9] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">8 </span></p> <p><strong>Explanation: </strong> We only have one choice for an increasing triplet and that is choosing all three elements. The value of this triplet would be <code>5 - 6 + 9 = 8</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> nums = [1,5,3,6] </span></p> <p><strong>Output:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 4 </span></p> <p><strong>Explanation: </strong> There are only two increasing triplets:</p> <p><code>(0, 1, 3)</code>: The value of this triplet is <code>nums[0] - nums[1] + nums[3] = 1 - 5 + 6 = 2</code>.</p> <p><code>(0, 2, 3)</code>: The value of this triplet is <code>nums[0] - nums[2] + nums[3] = 1 - 3 + 6 = 4</code>.</p> <p>Thus the answer would be <code>4</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that at least one triplet meets the given condition.</li> </ul>
Array; Ordered Set
Go
func maximumTripletValue(nums []int) (ans int) { n := len(nums) right := make([]int, n) right[n-1] = nums[n-1] for i := n - 2; i >= 0; i-- { right[i] = max(nums[i], right[i+1]) } ts := treemap.NewWithIntComparator() ts.Put(nums[0], nil) for j := 1; j < n-1; j++ { if right[j+1] > nums[j] { val, _ := ts.Floor(nums[j] - 1) if val != nil { ans = max(ans, val.(int)-nums[j]+right[j+1]) } } ts.Put(nums[j], nil) } return }
3,073
Maximum Increasing Triplet Value
Medium
<p>Given an array <code>nums</code>, return <em>the <strong>maximum value</strong> of a triplet</em> <code>(i, j, k)</code> <em>such that</em> <code>i &lt; j &lt; k</code> <em>and</em> <code>nums[i] &lt; nums[j] &lt; nums[k]</code>.</p> <p>The <strong>value</strong> of a triplet <code>(i, j, k)</code> is <code>nums[i] - nums[j] + nums[k]</code>.</p> <div id="gtx-trans" style="position: absolute; left: 274px; top: 102px;"> <div class="gtx-trans-icon"> </div> </div> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">nums = [5,6,9] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">8 </span></p> <p><strong>Explanation: </strong> We only have one choice for an increasing triplet and that is choosing all three elements. The value of this triplet would be <code>5 - 6 + 9 = 8</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> nums = [1,5,3,6] </span></p> <p><strong>Output:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 4 </span></p> <p><strong>Explanation: </strong> There are only two increasing triplets:</p> <p><code>(0, 1, 3)</code>: The value of this triplet is <code>nums[0] - nums[1] + nums[3] = 1 - 5 + 6 = 2</code>.</p> <p><code>(0, 2, 3)</code>: The value of this triplet is <code>nums[0] - nums[2] + nums[3] = 1 - 3 + 6 = 4</code>.</p> <p>Thus the answer would be <code>4</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that at least one triplet meets the given condition.</li> </ul>
Array; Ordered Set
Java
class Solution { public int maximumTripletValue(int[] nums) { int n = nums.length; int[] right = new int[n]; right[n - 1] = nums[n - 1]; for (int i = n - 2; i >= 0; --i) { right[i] = Math.max(nums[i], right[i + 1]); } TreeSet<Integer> ts = new TreeSet<>(); ts.add(nums[0]); int ans = 0; for (int j = 1; j < n - 1; ++j) { if (right[j + 1] > nums[j]) { Integer it = ts.lower(nums[j]); if (it != null) { ans = Math.max(ans, it - nums[j] + right[j + 1]); } } ts.add(nums[j]); } return ans; } }
3,073
Maximum Increasing Triplet Value
Medium
<p>Given an array <code>nums</code>, return <em>the <strong>maximum value</strong> of a triplet</em> <code>(i, j, k)</code> <em>such that</em> <code>i &lt; j &lt; k</code> <em>and</em> <code>nums[i] &lt; nums[j] &lt; nums[k]</code>.</p> <p>The <strong>value</strong> of a triplet <code>(i, j, k)</code> is <code>nums[i] - nums[j] + nums[k]</code>.</p> <div id="gtx-trans" style="position: absolute; left: 274px; top: 102px;"> <div class="gtx-trans-icon"> </div> </div> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">nums = [5,6,9] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">8 </span></p> <p><strong>Explanation: </strong> We only have one choice for an increasing triplet and that is choosing all three elements. The value of this triplet would be <code>5 - 6 + 9 = 8</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> nums = [1,5,3,6] </span></p> <p><strong>Output:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 4 </span></p> <p><strong>Explanation: </strong> There are only two increasing triplets:</p> <p><code>(0, 1, 3)</code>: The value of this triplet is <code>nums[0] - nums[1] + nums[3] = 1 - 5 + 6 = 2</code>.</p> <p><code>(0, 2, 3)</code>: The value of this triplet is <code>nums[0] - nums[2] + nums[3] = 1 - 3 + 6 = 4</code>.</p> <p>Thus the answer would be <code>4</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that at least one triplet meets the given condition.</li> </ul>
Array; Ordered Set
Python
class Solution: def maximumTripletValue(self, nums: List[int]) -> int: n = len(nums) right = [nums[-1]] * n for i in range(n - 2, -1, -1): right[i] = max(nums[i], right[i + 1]) sl = SortedList([nums[0]]) ans = 0 for j in range(1, n - 1): if right[j + 1] > nums[j]: i = sl.bisect_left(nums[j]) - 1 if i >= 0: ans = max(ans, sl[i] - nums[j] + right[j + 1]) sl.add(nums[j]) return ans
3,073
Maximum Increasing Triplet Value
Medium
<p>Given an array <code>nums</code>, return <em>the <strong>maximum value</strong> of a triplet</em> <code>(i, j, k)</code> <em>such that</em> <code>i &lt; j &lt; k</code> <em>and</em> <code>nums[i] &lt; nums[j] &lt; nums[k]</code>.</p> <p>The <strong>value</strong> of a triplet <code>(i, j, k)</code> is <code>nums[i] - nums[j] + nums[k]</code>.</p> <div id="gtx-trans" style="position: absolute; left: 274px; top: 102px;"> <div class="gtx-trans-icon"> </div> </div> <p>&nbsp;</p> <p><strong class="example">Example 1: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">nums = [5,6,9] </span></p> <p><strong>Output: </strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;">8 </span></p> <p><strong>Explanation: </strong> We only have one choice for an increasing triplet and that is choosing all three elements. The value of this triplet would be <code>5 - 6 + 9 = 8</code>.</p> </div> <p><strong class="example">Example 2: </strong></p> <div class="example-block" style="border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem;"> <p><strong>Input:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> nums = [1,5,3,6] </span></p> <p><strong>Output:</strong> <span class="example-io" style="font-family: Menlo,sans-serif; font-size: 0.85rem;"> 4 </span></p> <p><strong>Explanation: </strong> There are only two increasing triplets:</p> <p><code>(0, 1, 3)</code>: The value of this triplet is <code>nums[0] - nums[1] + nums[3] = 1 - 5 + 6 = 2</code>.</p> <p><code>(0, 2, 3)</code>: The value of this triplet is <code>nums[0] - nums[2] + nums[3] = 1 - 3 + 6 = 4</code>.</p> <p>Thus the answer would be <code>4</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>3 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li>The input is generated such that at least one triplet meets the given condition.</li> </ul>
Array; Ordered Set
TypeScript
function maximumTripletValue(nums: number[]): number { const n = nums.length; const right: number[] = Array(n).fill(nums[n - 1]); for (let i = n - 2; ~i; --i) { right[i] = Math.max(nums[i], right[i + 1]); } const ts = new TreeSet<number>(); ts.add(nums[0]); let ans = 0; for (let j = 1; j < n - 1; ++j) { if (right[j + 1] > nums[j]) { const val = ts.lower(nums[j]); if (val !== undefined) { ans = Math.max(ans, val - nums[j] + right[j + 1]); } } ts.add(nums[j]); } return ans; } type Compare<T> = (lhs: T, rhs: T) => number; class RBTreeNode<T = number> { data: T; count: number; left: RBTreeNode<T> | null; right: RBTreeNode<T> | null; parent: RBTreeNode<T> | null; color: number; constructor(data: T) { this.data = data; this.left = this.right = this.parent = null; this.color = 0; this.count = 1; } sibling(): RBTreeNode<T> | null { if (!this.parent) return null; // sibling null if no parent return this.isOnLeft() ? this.parent.right : this.parent.left; } isOnLeft(): boolean { return this === this.parent!.left; } hasRedChild(): boolean { return ( Boolean(this.left && this.left.color === 0) || Boolean(this.right && this.right.color === 0) ); } } class RBTree<T> { root: RBTreeNode<T> | null; lt: (l: T, r: T) => boolean; constructor(compare: Compare<T> = (l: T, r: T) => (l < r ? -1 : l > r ? 1 : 0)) { this.root = null; this.lt = (l: T, r: T) => compare(l, r) < 0; } rotateLeft(pt: RBTreeNode<T>): void { const right = pt.right!; pt.right = right.left; if (pt.right) pt.right.parent = pt; right.parent = pt.parent; if (!pt.parent) this.root = right; else if (pt === pt.parent.left) pt.parent.left = right; else pt.parent.right = right; right.left = pt; pt.parent = right; } rotateRight(pt: RBTreeNode<T>): void { const left = pt.left!; pt.left = left.right; if (pt.left) pt.left.parent = pt; left.parent = pt.parent; if (!pt.parent) this.root = left; else if (pt === pt.parent.left) pt.parent.left = left; else pt.parent.right = left; left.right = pt; pt.parent = left; } swapColor(p1: RBTreeNode<T>, p2: RBTreeNode<T>): void { const tmp = p1.color; p1.color = p2.color; p2.color = tmp; } swapData(p1: RBTreeNode<T>, p2: RBTreeNode<T>): void { const tmp = p1.data; p1.data = p2.data; p2.data = tmp; } fixAfterInsert(pt: RBTreeNode<T>): void { let parent = null; let grandParent = null; while (pt !== this.root && pt.color !== 1 && pt.parent?.color === 0) { parent = pt.parent; grandParent = pt.parent.parent; /* Case : A Parent of pt is left child of Grand-parent of pt */ if (parent === grandParent?.left) { const uncle = grandParent.right; /* Case : 1 The uncle of pt is also red Only Recoloring required */ if (uncle && uncle.color === 0) { grandParent.color = 0; parent.color = 1; uncle.color = 1; pt = grandParent; } else { /* Case : 2 pt is right child of its parent Left-rotation required */ if (pt === parent.right) { this.rotateLeft(parent); pt = parent; parent = pt.parent; } /* Case : 3 pt is left child of its parent Right-rotation required */ this.rotateRight(grandParent); this.swapColor(parent!, grandParent); pt = parent!; } } else { /* Case : B Parent of pt is right child of Grand-parent of pt */ const uncle = grandParent!.left; /* Case : 1 The uncle of pt is also red Only Recoloring required */ if (uncle != null && uncle.color === 0) { grandParent!.color = 0; parent.color = 1; uncle.color = 1; pt = grandParent!; } else { /* Case : 2 pt is left child of its parent Right-rotation required */ if (pt === parent.left) { this.rotateRight(parent); pt = parent; parent = pt.parent; } /* Case : 3 pt is right child of its parent Left-rotation required */ this.rotateLeft(grandParent!); this.swapColor(parent!, grandParent!); pt = parent!; } } } this.root!.color = 1; } delete(val: T): boolean { const node = this.find(val); if (!node) return false; node.count--; if (!node.count) this.deleteNode(node); return true; } deleteAll(val: T): boolean { const node = this.find(val); if (!node) return false; this.deleteNode(node); return true; } deleteNode(v: RBTreeNode<T>): void { const u = BSTreplace(v); // True when u and v are both black const uvBlack = (u === null || u.color === 1) && v.color === 1; const parent = v.parent!; if (!u) { // u is null therefore v is leaf if (v === this.root) this.root = null; // v is root, making root null else { if (uvBlack) { // u and v both black // v is leaf, fix double black at v this.fixDoubleBlack(v); } else { // u or v is red if (v.sibling()) { // sibling is not null, make it red" v.sibling()!.color = 0; } } // delete v from the tree if (v.isOnLeft()) parent.left = null; else parent.right = null; } return; } if (!v.left || !v.right) { // v has 1 child if (v === this.root) { // v is root, assign the value of u to v, and delete u v.data = u.data; v.left = v.right = null; } else { // Detach v from tree and move u up if (v.isOnLeft()) parent.left = u; else parent.right = u; u.parent = parent; if (uvBlack) this.fixDoubleBlack(u); // u and v both black, fix double black at u else u.color = 1; // u or v red, color u black } return; } // v has 2 children, swap data with successor and recurse this.swapData(u, v); this.deleteNode(u); // find node that replaces a deleted node in BST function BSTreplace(x: RBTreeNode<T>): RBTreeNode<T> | null { // when node have 2 children if (x.left && x.right) return successor(x.right); // when leaf if (!x.left && !x.right) return null; // when single child return x.left ?? x.right; } // find node that do not have a left child // in the subtree of the given node function successor(x: RBTreeNode<T>): RBTreeNode<T> { let temp = x; while (temp.left) temp = temp.left; return temp; } } fixDoubleBlack(x: RBTreeNode<T>): void { if (x === this.root) return; // Reached root const sibling = x.sibling(); const parent = x.parent!; if (!sibling) { // No sibiling, double black pushed up this.fixDoubleBlack(parent); } else { if (sibling.color === 0) { // Sibling red parent.color = 0; sibling.color = 1; if (sibling.isOnLeft()) this.rotateRight(parent); // left case else this.rotateLeft(parent); // right case this.fixDoubleBlack(x); } else { // Sibling black if (sibling.hasRedChild()) { // at least 1 red children if (sibling.left && sibling.left.color === 0) { if (sibling.isOnLeft()) { // left left sibling.left.color = sibling.color; sibling.color = parent.color; this.rotateRight(parent); } else { // right left sibling.left.color = parent.color; this.rotateRight(sibling); this.rotateLeft(parent); } } else { if (sibling.isOnLeft()) { // left right sibling.right!.color = parent.color; this.rotateLeft(sibling); this.rotateRight(parent); } else { // right right sibling.right!.color = sibling.color; sibling.color = parent.color; this.rotateLeft(parent); } } parent.color = 1; } else { // 2 black children sibling.color = 0; if (parent.color === 1) this.fixDoubleBlack(parent); else parent.color = 1; } } } } insert(data: T): boolean { // search for a position to insert let parent = this.root; while (parent) { if (this.lt(data, parent.data)) { if (!parent.left) break; else parent = parent.left; } else if (this.lt(parent.data, data)) { if (!parent.right) break; else parent = parent.right; } else break; } // insert node into parent const node = new RBTreeNode(data); if (!parent) this.root = node; else if (this.lt(node.data, parent.data)) parent.left = node; else if (this.lt(parent.data, node.data)) parent.right = node; else { parent.count++; return false; } node.parent = parent; this.fixAfterInsert(node); return true; } find(data: T): RBTreeNode<T> | null { let p = this.root; while (p) { if (this.lt(data, p.data)) { p = p.left; } else if (this.lt(p.data, data)) { p = p.right; } else break; } return p ?? null; } *inOrder(root: RBTreeNode<T> = this.root!): Generator<T, undefined, void> { if (!root) return; for (const v of this.inOrder(root.left!)) yield v; yield root.data; for (const v of this.inOrder(root.right!)) yield v; } *reverseInOrder(root: RBTreeNode<T> = this.root!): Generator<T, undefined, void> { if (!root) return; for (const v of this.reverseInOrder(root.right!)) yield v; yield root.data; for (const v of this.reverseInOrder(root.left!)) yield v; } } class TreeSet<T = number> { _size: number; tree: RBTree<T>; compare: Compare<T>; constructor( collection: T[] | Compare<T> = [], compare: Compare<T> = (l: T, r: T) => (l < r ? -1 : l > r ? 1 : 0), ) { if (typeof collection === 'function') { compare = collection; collection = []; } this._size = 0; this.compare = compare; this.tree = new RBTree(compare); for (const val of collection) this.add(val); } size(): number { return this._size; } has(val: T): boolean { return !!this.tree.find(val); } add(val: T): boolean { const successful = this.tree.insert(val); this._size += successful ? 1 : 0; return successful; } delete(val: T): boolean { const deleted = this.tree.deleteAll(val); this._size -= deleted ? 1 : 0; return deleted; } ceil(val: T): T | undefined { let p = this.tree.root; let higher = null; while (p) { if (this.compare(p.data, val) >= 0) { higher = p; p = p.left; } else { p = p.right; } } return higher?.data; } floor(val: T): T | undefined { let p = this.tree.root; let lower = null; while (p) { if (this.compare(val, p.data) >= 0) { lower = p; p = p.right; } else { p = p.left; } } return lower?.data; } higher(val: T): T | undefined { let p = this.tree.root; let higher = null; while (p) { if (this.compare(val, p.data) < 0) { higher = p; p = p.left; } else { p = p.right; } } return higher?.data; } lower(val: T): T | undefined { let p = this.tree.root; let lower = null; while (p) { if (this.compare(p.data, val) < 0) { lower = p; p = p.right; } else { p = p.left; } } return lower?.data; } first(): T | undefined { return this.tree.inOrder().next().value; } last(): T | undefined { return this.tree.reverseInOrder().next().value; } shift(): T | undefined { const first = this.first(); if (first === undefined) return undefined; this.delete(first); return first; } pop(): T | undefined { const last = this.last(); if (last === undefined) return undefined; this.delete(last); return last; } *[Symbol.iterator](): Generator<T, void, void> { for (const val of this.values()) yield val; } *keys(): Generator<T, void, void> { for (const val of this.values()) yield val; } *values(): Generator<T, undefined, void> { for (const val of this.tree.inOrder()) yield val; return undefined; } /** * Return a generator for reverse order traversing the set */ *rvalues(): Generator<T, undefined, void> { for (const val of this.tree.reverseInOrder()) yield val; return undefined; } }
3,074
Apple Redistribution into Boxes
Easy
<p>You are given an array <code>apple</code> of size <code>n</code> and an array <code>capacity</code> of size <code>m</code>.</p> <p>There are <code>n</code> packs where the <code>i<sup>th</sup></code> pack contains <code>apple[i]</code> apples. There are <code>m</code> boxes as well, and the <code>i<sup>th</sup></code> box has a capacity of <code>capacity[i]</code> apples.</p> <p>Return <em>the <strong>minimum</strong> number of boxes you need to select to redistribute these </em><code>n</code><em> packs of apples into boxes</em>.</p> <p><strong>Note</strong> that, apples from the same pack can be distributed into different boxes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> apple = [1,3,2], capacity = [4,3,1,5,2] <strong>Output:</strong> 2 <strong>Explanation:</strong> We will use boxes with capacities 4 and 5. It is possible to distribute the apples as the total capacity is greater than or equal to the total number of apples. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> apple = [5,5,5], capacity = [2,4,2,7] <strong>Output:</strong> 4 <strong>Explanation:</strong> We will need to use all the boxes. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == apple.length &lt;= 50</code></li> <li><code>1 &lt;= m == capacity.length &lt;= 50</code></li> <li><code>1 &lt;= apple[i], capacity[i] &lt;= 50</code></li> <li>The input is generated such that it&#39;s possible to redistribute packs of apples into boxes.</li> </ul>
Greedy; Array; Sorting
C++
class Solution { public: int minimumBoxes(vector<int>& apple, vector<int>& capacity) { sort(capacity.rbegin(), capacity.rend()); int s = accumulate(apple.begin(), apple.end(), 0); for (int i = 1;; ++i) { s -= capacity[i - 1]; if (s <= 0) { return i; } } } };
3,074
Apple Redistribution into Boxes
Easy
<p>You are given an array <code>apple</code> of size <code>n</code> and an array <code>capacity</code> of size <code>m</code>.</p> <p>There are <code>n</code> packs where the <code>i<sup>th</sup></code> pack contains <code>apple[i]</code> apples. There are <code>m</code> boxes as well, and the <code>i<sup>th</sup></code> box has a capacity of <code>capacity[i]</code> apples.</p> <p>Return <em>the <strong>minimum</strong> number of boxes you need to select to redistribute these </em><code>n</code><em> packs of apples into boxes</em>.</p> <p><strong>Note</strong> that, apples from the same pack can be distributed into different boxes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> apple = [1,3,2], capacity = [4,3,1,5,2] <strong>Output:</strong> 2 <strong>Explanation:</strong> We will use boxes with capacities 4 and 5. It is possible to distribute the apples as the total capacity is greater than or equal to the total number of apples. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> apple = [5,5,5], capacity = [2,4,2,7] <strong>Output:</strong> 4 <strong>Explanation:</strong> We will need to use all the boxes. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == apple.length &lt;= 50</code></li> <li><code>1 &lt;= m == capacity.length &lt;= 50</code></li> <li><code>1 &lt;= apple[i], capacity[i] &lt;= 50</code></li> <li>The input is generated such that it&#39;s possible to redistribute packs of apples into boxes.</li> </ul>
Greedy; Array; Sorting
Go
func minimumBoxes(apple []int, capacity []int) int { sort.Ints(capacity) s := 0 for _, x := range apple { s += x } for i := 1; ; i++ { s -= capacity[len(capacity)-i] if s <= 0 { return i } } }
3,074
Apple Redistribution into Boxes
Easy
<p>You are given an array <code>apple</code> of size <code>n</code> and an array <code>capacity</code> of size <code>m</code>.</p> <p>There are <code>n</code> packs where the <code>i<sup>th</sup></code> pack contains <code>apple[i]</code> apples. There are <code>m</code> boxes as well, and the <code>i<sup>th</sup></code> box has a capacity of <code>capacity[i]</code> apples.</p> <p>Return <em>the <strong>minimum</strong> number of boxes you need to select to redistribute these </em><code>n</code><em> packs of apples into boxes</em>.</p> <p><strong>Note</strong> that, apples from the same pack can be distributed into different boxes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> apple = [1,3,2], capacity = [4,3,1,5,2] <strong>Output:</strong> 2 <strong>Explanation:</strong> We will use boxes with capacities 4 and 5. It is possible to distribute the apples as the total capacity is greater than or equal to the total number of apples. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> apple = [5,5,5], capacity = [2,4,2,7] <strong>Output:</strong> 4 <strong>Explanation:</strong> We will need to use all the boxes. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == apple.length &lt;= 50</code></li> <li><code>1 &lt;= m == capacity.length &lt;= 50</code></li> <li><code>1 &lt;= apple[i], capacity[i] &lt;= 50</code></li> <li>The input is generated such that it&#39;s possible to redistribute packs of apples into boxes.</li> </ul>
Greedy; Array; Sorting
Java
class Solution { public int minimumBoxes(int[] apple, int[] capacity) { Arrays.sort(capacity); int s = 0; for (int x : apple) { s += x; } for (int i = 1, n = capacity.length;; ++i) { s -= capacity[n - i]; if (s <= 0) { return i; } } } }
3,074
Apple Redistribution into Boxes
Easy
<p>You are given an array <code>apple</code> of size <code>n</code> and an array <code>capacity</code> of size <code>m</code>.</p> <p>There are <code>n</code> packs where the <code>i<sup>th</sup></code> pack contains <code>apple[i]</code> apples. There are <code>m</code> boxes as well, and the <code>i<sup>th</sup></code> box has a capacity of <code>capacity[i]</code> apples.</p> <p>Return <em>the <strong>minimum</strong> number of boxes you need to select to redistribute these </em><code>n</code><em> packs of apples into boxes</em>.</p> <p><strong>Note</strong> that, apples from the same pack can be distributed into different boxes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> apple = [1,3,2], capacity = [4,3,1,5,2] <strong>Output:</strong> 2 <strong>Explanation:</strong> We will use boxes with capacities 4 and 5. It is possible to distribute the apples as the total capacity is greater than or equal to the total number of apples. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> apple = [5,5,5], capacity = [2,4,2,7] <strong>Output:</strong> 4 <strong>Explanation:</strong> We will need to use all the boxes. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == apple.length &lt;= 50</code></li> <li><code>1 &lt;= m == capacity.length &lt;= 50</code></li> <li><code>1 &lt;= apple[i], capacity[i] &lt;= 50</code></li> <li>The input is generated such that it&#39;s possible to redistribute packs of apples into boxes.</li> </ul>
Greedy; Array; Sorting
Python
class Solution: def minimumBoxes(self, apple: List[int], capacity: List[int]) -> int: capacity.sort(reverse=True) s = sum(apple) for i, c in enumerate(capacity, 1): s -= c if s <= 0: return i
3,074
Apple Redistribution into Boxes
Easy
<p>You are given an array <code>apple</code> of size <code>n</code> and an array <code>capacity</code> of size <code>m</code>.</p> <p>There are <code>n</code> packs where the <code>i<sup>th</sup></code> pack contains <code>apple[i]</code> apples. There are <code>m</code> boxes as well, and the <code>i<sup>th</sup></code> box has a capacity of <code>capacity[i]</code> apples.</p> <p>Return <em>the <strong>minimum</strong> number of boxes you need to select to redistribute these </em><code>n</code><em> packs of apples into boxes</em>.</p> <p><strong>Note</strong> that, apples from the same pack can be distributed into different boxes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> apple = [1,3,2], capacity = [4,3,1,5,2] <strong>Output:</strong> 2 <strong>Explanation:</strong> We will use boxes with capacities 4 and 5. It is possible to distribute the apples as the total capacity is greater than or equal to the total number of apples. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> apple = [5,5,5], capacity = [2,4,2,7] <strong>Output:</strong> 4 <strong>Explanation:</strong> We will need to use all the boxes. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == apple.length &lt;= 50</code></li> <li><code>1 &lt;= m == capacity.length &lt;= 50</code></li> <li><code>1 &lt;= apple[i], capacity[i] &lt;= 50</code></li> <li>The input is generated such that it&#39;s possible to redistribute packs of apples into boxes.</li> </ul>
Greedy; Array; Sorting
TypeScript
function minimumBoxes(apple: number[], capacity: number[]): number { capacity.sort((a, b) => b - a); let s = apple.reduce((acc, cur) => acc + cur, 0); for (let i = 1; ; ++i) { s -= capacity[i - 1]; if (s <= 0) { return i; } } }
3,075
Maximize Happiness of Selected Children
Medium
<p>You are given an array <code>happiness</code> of length <code>n</code>, and a <strong>positive</strong> integer <code>k</code>.</p> <p>There are <code>n</code> children standing in a queue, where the <code>i<sup>th</sup></code> child has <strong>happiness value</strong> <code>happiness[i]</code>. You want to select <code>k</code> children from these <code>n</code> children in <code>k</code> turns.</p> <p>In each turn, when you select a child, the <strong>happiness value</strong> of all the children that have <strong>not</strong> been selected till now decreases by <code>1</code>. Note that the happiness value <strong>cannot</strong> become negative and gets decremented <strong>only</strong> if it is positive.</p> <p>Return <em>the <strong>maximum</strong> sum of the happiness values of the selected children you can achieve by selecting </em><code>k</code> <em>children</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> happiness = [1,2,3], k = 2 <strong>Output:</strong> 4 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick the child with the happiness value == 3. The happiness value of the remaining children becomes [0,1]. - Pick the child with the happiness value == 1. The happiness value of the remaining child becomes [0]. Note that the happiness value cannot become less than 0. The sum of the happiness values of the selected children is 3 + 1 = 4. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> happiness = [1,1,1,1], k = 2 <strong>Output:</strong> 1 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick any child with the happiness value == 1. The happiness value of the remaining children becomes [0,0,0]. - Pick the child with the happiness value == 0. The happiness value of the remaining child becomes [0,0]. The sum of the happiness values of the selected children is 1 + 0 = 1. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> happiness = [2,3,4,5], k = 1 <strong>Output:</strong> 5 <strong>Explanation:</strong> We can pick 1 child in the following way: - Pick the child with the happiness value == 5. The happiness value of the remaining children becomes [1,2,3]. The sum of the happiness values of the selected children is 5. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == happiness.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= happiness[i] &lt;= 10<sup>8</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Greedy; Array; Sorting
C++
class Solution { public: long long maximumHappinessSum(vector<int>& happiness, int k) { sort(happiness.rbegin(), happiness.rend()); long long ans = 0; for (int i = 0, n = happiness.size(); i < k; ++i) { int x = happiness[i] - i; ans += max(x, 0); } return ans; } };
3,075
Maximize Happiness of Selected Children
Medium
<p>You are given an array <code>happiness</code> of length <code>n</code>, and a <strong>positive</strong> integer <code>k</code>.</p> <p>There are <code>n</code> children standing in a queue, where the <code>i<sup>th</sup></code> child has <strong>happiness value</strong> <code>happiness[i]</code>. You want to select <code>k</code> children from these <code>n</code> children in <code>k</code> turns.</p> <p>In each turn, when you select a child, the <strong>happiness value</strong> of all the children that have <strong>not</strong> been selected till now decreases by <code>1</code>. Note that the happiness value <strong>cannot</strong> become negative and gets decremented <strong>only</strong> if it is positive.</p> <p>Return <em>the <strong>maximum</strong> sum of the happiness values of the selected children you can achieve by selecting </em><code>k</code> <em>children</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> happiness = [1,2,3], k = 2 <strong>Output:</strong> 4 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick the child with the happiness value == 3. The happiness value of the remaining children becomes [0,1]. - Pick the child with the happiness value == 1. The happiness value of the remaining child becomes [0]. Note that the happiness value cannot become less than 0. The sum of the happiness values of the selected children is 3 + 1 = 4. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> happiness = [1,1,1,1], k = 2 <strong>Output:</strong> 1 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick any child with the happiness value == 1. The happiness value of the remaining children becomes [0,0,0]. - Pick the child with the happiness value == 0. The happiness value of the remaining child becomes [0,0]. The sum of the happiness values of the selected children is 1 + 0 = 1. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> happiness = [2,3,4,5], k = 1 <strong>Output:</strong> 5 <strong>Explanation:</strong> We can pick 1 child in the following way: - Pick the child with the happiness value == 5. The happiness value of the remaining children becomes [1,2,3]. The sum of the happiness values of the selected children is 5. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == happiness.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= happiness[i] &lt;= 10<sup>8</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Greedy; Array; Sorting
Go
func maximumHappinessSum(happiness []int, k int) (ans int64) { sort.Ints(happiness) for i := 0; i < k; i++ { x := happiness[len(happiness)-i-1] - i ans += int64(max(x, 0)) } return }
3,075
Maximize Happiness of Selected Children
Medium
<p>You are given an array <code>happiness</code> of length <code>n</code>, and a <strong>positive</strong> integer <code>k</code>.</p> <p>There are <code>n</code> children standing in a queue, where the <code>i<sup>th</sup></code> child has <strong>happiness value</strong> <code>happiness[i]</code>. You want to select <code>k</code> children from these <code>n</code> children in <code>k</code> turns.</p> <p>In each turn, when you select a child, the <strong>happiness value</strong> of all the children that have <strong>not</strong> been selected till now decreases by <code>1</code>. Note that the happiness value <strong>cannot</strong> become negative and gets decremented <strong>only</strong> if it is positive.</p> <p>Return <em>the <strong>maximum</strong> sum of the happiness values of the selected children you can achieve by selecting </em><code>k</code> <em>children</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> happiness = [1,2,3], k = 2 <strong>Output:</strong> 4 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick the child with the happiness value == 3. The happiness value of the remaining children becomes [0,1]. - Pick the child with the happiness value == 1. The happiness value of the remaining child becomes [0]. Note that the happiness value cannot become less than 0. The sum of the happiness values of the selected children is 3 + 1 = 4. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> happiness = [1,1,1,1], k = 2 <strong>Output:</strong> 1 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick any child with the happiness value == 1. The happiness value of the remaining children becomes [0,0,0]. - Pick the child with the happiness value == 0. The happiness value of the remaining child becomes [0,0]. The sum of the happiness values of the selected children is 1 + 0 = 1. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> happiness = [2,3,4,5], k = 1 <strong>Output:</strong> 5 <strong>Explanation:</strong> We can pick 1 child in the following way: - Pick the child with the happiness value == 5. The happiness value of the remaining children becomes [1,2,3]. The sum of the happiness values of the selected children is 5. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == happiness.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= happiness[i] &lt;= 10<sup>8</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Greedy; Array; Sorting
Java
class Solution { public long maximumHappinessSum(int[] happiness, int k) { Arrays.sort(happiness); long ans = 0; for (int i = 0, n = happiness.length; i < k; ++i) { int x = happiness[n - i - 1] - i; ans += Math.max(x, 0); } return ans; } }
3,075
Maximize Happiness of Selected Children
Medium
<p>You are given an array <code>happiness</code> of length <code>n</code>, and a <strong>positive</strong> integer <code>k</code>.</p> <p>There are <code>n</code> children standing in a queue, where the <code>i<sup>th</sup></code> child has <strong>happiness value</strong> <code>happiness[i]</code>. You want to select <code>k</code> children from these <code>n</code> children in <code>k</code> turns.</p> <p>In each turn, when you select a child, the <strong>happiness value</strong> of all the children that have <strong>not</strong> been selected till now decreases by <code>1</code>. Note that the happiness value <strong>cannot</strong> become negative and gets decremented <strong>only</strong> if it is positive.</p> <p>Return <em>the <strong>maximum</strong> sum of the happiness values of the selected children you can achieve by selecting </em><code>k</code> <em>children</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> happiness = [1,2,3], k = 2 <strong>Output:</strong> 4 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick the child with the happiness value == 3. The happiness value of the remaining children becomes [0,1]. - Pick the child with the happiness value == 1. The happiness value of the remaining child becomes [0]. Note that the happiness value cannot become less than 0. The sum of the happiness values of the selected children is 3 + 1 = 4. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> happiness = [1,1,1,1], k = 2 <strong>Output:</strong> 1 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick any child with the happiness value == 1. The happiness value of the remaining children becomes [0,0,0]. - Pick the child with the happiness value == 0. The happiness value of the remaining child becomes [0,0]. The sum of the happiness values of the selected children is 1 + 0 = 1. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> happiness = [2,3,4,5], k = 1 <strong>Output:</strong> 5 <strong>Explanation:</strong> We can pick 1 child in the following way: - Pick the child with the happiness value == 5. The happiness value of the remaining children becomes [1,2,3]. The sum of the happiness values of the selected children is 5. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == happiness.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= happiness[i] &lt;= 10<sup>8</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Greedy; Array; Sorting
Python
class Solution: def maximumHappinessSum(self, happiness: List[int], k: int) -> int: happiness.sort(reverse=True) ans = 0 for i, x in enumerate(happiness[:k]): x -= i ans += max(x, 0) return ans
3,075
Maximize Happiness of Selected Children
Medium
<p>You are given an array <code>happiness</code> of length <code>n</code>, and a <strong>positive</strong> integer <code>k</code>.</p> <p>There are <code>n</code> children standing in a queue, where the <code>i<sup>th</sup></code> child has <strong>happiness value</strong> <code>happiness[i]</code>. You want to select <code>k</code> children from these <code>n</code> children in <code>k</code> turns.</p> <p>In each turn, when you select a child, the <strong>happiness value</strong> of all the children that have <strong>not</strong> been selected till now decreases by <code>1</code>. Note that the happiness value <strong>cannot</strong> become negative and gets decremented <strong>only</strong> if it is positive.</p> <p>Return <em>the <strong>maximum</strong> sum of the happiness values of the selected children you can achieve by selecting </em><code>k</code> <em>children</em>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> happiness = [1,2,3], k = 2 <strong>Output:</strong> 4 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick the child with the happiness value == 3. The happiness value of the remaining children becomes [0,1]. - Pick the child with the happiness value == 1. The happiness value of the remaining child becomes [0]. Note that the happiness value cannot become less than 0. The sum of the happiness values of the selected children is 3 + 1 = 4. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> happiness = [1,1,1,1], k = 2 <strong>Output:</strong> 1 <strong>Explanation:</strong> We can pick 2 children in the following way: - Pick any child with the happiness value == 1. The happiness value of the remaining children becomes [0,0,0]. - Pick the child with the happiness value == 0. The happiness value of the remaining child becomes [0,0]. The sum of the happiness values of the selected children is 1 + 0 = 1. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> happiness = [2,3,4,5], k = 1 <strong>Output:</strong> 5 <strong>Explanation:</strong> We can pick 1 child in the following way: - Pick the child with the happiness value == 5. The happiness value of the remaining children becomes [1,2,3]. The sum of the happiness values of the selected children is 5. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == happiness.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= happiness[i] &lt;= 10<sup>8</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Greedy; Array; Sorting
TypeScript
function maximumHappinessSum(happiness: number[], k: number): number { happiness.sort((a, b) => b - a); let ans = 0; for (let i = 0; i < k; ++i) { const x = happiness[i] - i; ans += Math.max(x, 0); } return ans; }
3,076
Shortest Uncommon Substring in an Array
Medium
<p>You are given an array <code>arr</code> of size <code>n</code> consisting of <strong>non-empty</strong> strings.</p> <p>Find a string array <code>answer</code> of size <code>n</code> such that:</p> <ul> <li><code>answer[i]</code> is the <strong>shortest</strong> <span data-keyword="substring">substring</span> of <code>arr[i]</code> that does <strong>not</strong> occur as a substring in any other string in <code>arr</code>. If multiple such substrings exist, <code>answer[i]</code> should be the <span data-keyword="lexicographically-smaller-string">lexicographically smallest</span>. And if no such substring exists, <code>answer[i]</code> should be an empty string.</li> </ul> <p>Return <em>the array </em><code>answer</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;cab&quot;,&quot;ad&quot;,&quot;bad&quot;,&quot;c&quot;] <strong>Output:</strong> [&quot;ab&quot;,&quot;&quot;,&quot;ba&quot;,&quot;&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;cab&quot;, the shortest substring that does not occur in any other string is either &quot;ca&quot; or &quot;ab&quot;, we choose the lexicographically smaller substring, which is &quot;ab&quot;. - For the string &quot;ad&quot;, there is no substring that does not occur in any other string. - For the string &quot;bad&quot;, the shortest substring that does not occur in any other string is &quot;ba&quot;. - For the string &quot;c&quot;, there is no substring that does not occur in any other string. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;abc&quot;,&quot;bcd&quot;,&quot;abcd&quot;] <strong>Output:</strong> [&quot;&quot;,&quot;&quot;,&quot;abcd&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;abc&quot;, there is no substring that does not occur in any other string. - For the string &quot;bcd&quot;, there is no substring that does not occur in any other string. - For the string &quot;abcd&quot;, the shortest substring that does not occur in any other string is &quot;abcd&quot;. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == arr.length</code></li> <li><code>2 &lt;= n &lt;= 100</code></li> <li><code>1 &lt;= arr[i].length &lt;= 20</code></li> <li><code>arr[i]</code> consists only of lowercase English letters.</li> </ul>
Trie; Array; Hash Table; String
C++
class Solution { public: vector<string> shortestSubstrings(vector<string>& arr) { int n = arr.size(); vector<string> ans(n); for (int i = 0; i < n; ++i) { int m = arr[i].size(); for (int j = 1; j <= m && ans[i].empty(); ++j) { for (int l = 0; l <= m - j; ++l) { string sub = arr[i].substr(l, j); if (ans[i].empty() || sub < ans[i]) { bool ok = true; for (int k = 0; k < n && ok; ++k) { if (k != i && arr[k].find(sub) != string::npos) { ok = false; } } if (ok) { ans[i] = sub; } } } } } return ans; } };
3,076
Shortest Uncommon Substring in an Array
Medium
<p>You are given an array <code>arr</code> of size <code>n</code> consisting of <strong>non-empty</strong> strings.</p> <p>Find a string array <code>answer</code> of size <code>n</code> such that:</p> <ul> <li><code>answer[i]</code> is the <strong>shortest</strong> <span data-keyword="substring">substring</span> of <code>arr[i]</code> that does <strong>not</strong> occur as a substring in any other string in <code>arr</code>. If multiple such substrings exist, <code>answer[i]</code> should be the <span data-keyword="lexicographically-smaller-string">lexicographically smallest</span>. And if no such substring exists, <code>answer[i]</code> should be an empty string.</li> </ul> <p>Return <em>the array </em><code>answer</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;cab&quot;,&quot;ad&quot;,&quot;bad&quot;,&quot;c&quot;] <strong>Output:</strong> [&quot;ab&quot;,&quot;&quot;,&quot;ba&quot;,&quot;&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;cab&quot;, the shortest substring that does not occur in any other string is either &quot;ca&quot; or &quot;ab&quot;, we choose the lexicographically smaller substring, which is &quot;ab&quot;. - For the string &quot;ad&quot;, there is no substring that does not occur in any other string. - For the string &quot;bad&quot;, the shortest substring that does not occur in any other string is &quot;ba&quot;. - For the string &quot;c&quot;, there is no substring that does not occur in any other string. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;abc&quot;,&quot;bcd&quot;,&quot;abcd&quot;] <strong>Output:</strong> [&quot;&quot;,&quot;&quot;,&quot;abcd&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;abc&quot;, there is no substring that does not occur in any other string. - For the string &quot;bcd&quot;, there is no substring that does not occur in any other string. - For the string &quot;abcd&quot;, the shortest substring that does not occur in any other string is &quot;abcd&quot;. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == arr.length</code></li> <li><code>2 &lt;= n &lt;= 100</code></li> <li><code>1 &lt;= arr[i].length &lt;= 20</code></li> <li><code>arr[i]</code> consists only of lowercase English letters.</li> </ul>
Trie; Array; Hash Table; String
Go
func shortestSubstrings(arr []string) []string { ans := make([]string, len(arr)) for i, s := range arr { m := len(s) for j := 1; j <= m && len(ans[i]) == 0; j++ { for l := 0; l <= m-j; l++ { sub := s[l : l+j] if len(ans[i]) == 0 || ans[i] > sub { ok := true for k, t := range arr { if k != i && strings.Contains(t, sub) { ok = false break } } if ok { ans[i] = sub } } } } } return ans }
3,076
Shortest Uncommon Substring in an Array
Medium
<p>You are given an array <code>arr</code> of size <code>n</code> consisting of <strong>non-empty</strong> strings.</p> <p>Find a string array <code>answer</code> of size <code>n</code> such that:</p> <ul> <li><code>answer[i]</code> is the <strong>shortest</strong> <span data-keyword="substring">substring</span> of <code>arr[i]</code> that does <strong>not</strong> occur as a substring in any other string in <code>arr</code>. If multiple such substrings exist, <code>answer[i]</code> should be the <span data-keyword="lexicographically-smaller-string">lexicographically smallest</span>. And if no such substring exists, <code>answer[i]</code> should be an empty string.</li> </ul> <p>Return <em>the array </em><code>answer</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;cab&quot;,&quot;ad&quot;,&quot;bad&quot;,&quot;c&quot;] <strong>Output:</strong> [&quot;ab&quot;,&quot;&quot;,&quot;ba&quot;,&quot;&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;cab&quot;, the shortest substring that does not occur in any other string is either &quot;ca&quot; or &quot;ab&quot;, we choose the lexicographically smaller substring, which is &quot;ab&quot;. - For the string &quot;ad&quot;, there is no substring that does not occur in any other string. - For the string &quot;bad&quot;, the shortest substring that does not occur in any other string is &quot;ba&quot;. - For the string &quot;c&quot;, there is no substring that does not occur in any other string. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;abc&quot;,&quot;bcd&quot;,&quot;abcd&quot;] <strong>Output:</strong> [&quot;&quot;,&quot;&quot;,&quot;abcd&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;abc&quot;, there is no substring that does not occur in any other string. - For the string &quot;bcd&quot;, there is no substring that does not occur in any other string. - For the string &quot;abcd&quot;, the shortest substring that does not occur in any other string is &quot;abcd&quot;. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == arr.length</code></li> <li><code>2 &lt;= n &lt;= 100</code></li> <li><code>1 &lt;= arr[i].length &lt;= 20</code></li> <li><code>arr[i]</code> consists only of lowercase English letters.</li> </ul>
Trie; Array; Hash Table; String
Java
class Solution { public String[] shortestSubstrings(String[] arr) { int n = arr.length; String[] ans = new String[n]; Arrays.fill(ans, ""); for (int i = 0; i < n; ++i) { int m = arr[i].length(); for (int j = 1; j <= m && ans[i].isEmpty(); ++j) { for (int l = 0; l <= m - j; ++l) { String sub = arr[i].substring(l, l + j); if (ans[i].isEmpty() || sub.compareTo(ans[i]) < 0) { boolean ok = true; for (int k = 0; k < n && ok; ++k) { if (k != i && arr[k].contains(sub)) { ok = false; } } if (ok) { ans[i] = sub; } } } } } return ans; } }
3,076
Shortest Uncommon Substring in an Array
Medium
<p>You are given an array <code>arr</code> of size <code>n</code> consisting of <strong>non-empty</strong> strings.</p> <p>Find a string array <code>answer</code> of size <code>n</code> such that:</p> <ul> <li><code>answer[i]</code> is the <strong>shortest</strong> <span data-keyword="substring">substring</span> of <code>arr[i]</code> that does <strong>not</strong> occur as a substring in any other string in <code>arr</code>. If multiple such substrings exist, <code>answer[i]</code> should be the <span data-keyword="lexicographically-smaller-string">lexicographically smallest</span>. And if no such substring exists, <code>answer[i]</code> should be an empty string.</li> </ul> <p>Return <em>the array </em><code>answer</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;cab&quot;,&quot;ad&quot;,&quot;bad&quot;,&quot;c&quot;] <strong>Output:</strong> [&quot;ab&quot;,&quot;&quot;,&quot;ba&quot;,&quot;&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;cab&quot;, the shortest substring that does not occur in any other string is either &quot;ca&quot; or &quot;ab&quot;, we choose the lexicographically smaller substring, which is &quot;ab&quot;. - For the string &quot;ad&quot;, there is no substring that does not occur in any other string. - For the string &quot;bad&quot;, the shortest substring that does not occur in any other string is &quot;ba&quot;. - For the string &quot;c&quot;, there is no substring that does not occur in any other string. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;abc&quot;,&quot;bcd&quot;,&quot;abcd&quot;] <strong>Output:</strong> [&quot;&quot;,&quot;&quot;,&quot;abcd&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;abc&quot;, there is no substring that does not occur in any other string. - For the string &quot;bcd&quot;, there is no substring that does not occur in any other string. - For the string &quot;abcd&quot;, the shortest substring that does not occur in any other string is &quot;abcd&quot;. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == arr.length</code></li> <li><code>2 &lt;= n &lt;= 100</code></li> <li><code>1 &lt;= arr[i].length &lt;= 20</code></li> <li><code>arr[i]</code> consists only of lowercase English letters.</li> </ul>
Trie; Array; Hash Table; String
Python
class Solution: def shortestSubstrings(self, arr: List[str]) -> List[str]: ans = [""] * len(arr) for i, s in enumerate(arr): m = len(s) for j in range(1, m + 1): for l in range(m - j + 1): sub = s[l : l + j] if not ans[i] or ans[i] > sub: if all(k == i or sub not in t for k, t in enumerate(arr)): ans[i] = sub if ans[i]: break return ans
3,076
Shortest Uncommon Substring in an Array
Medium
<p>You are given an array <code>arr</code> of size <code>n</code> consisting of <strong>non-empty</strong> strings.</p> <p>Find a string array <code>answer</code> of size <code>n</code> such that:</p> <ul> <li><code>answer[i]</code> is the <strong>shortest</strong> <span data-keyword="substring">substring</span> of <code>arr[i]</code> that does <strong>not</strong> occur as a substring in any other string in <code>arr</code>. If multiple such substrings exist, <code>answer[i]</code> should be the <span data-keyword="lexicographically-smaller-string">lexicographically smallest</span>. And if no such substring exists, <code>answer[i]</code> should be an empty string.</li> </ul> <p>Return <em>the array </em><code>answer</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;cab&quot;,&quot;ad&quot;,&quot;bad&quot;,&quot;c&quot;] <strong>Output:</strong> [&quot;ab&quot;,&quot;&quot;,&quot;ba&quot;,&quot;&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;cab&quot;, the shortest substring that does not occur in any other string is either &quot;ca&quot; or &quot;ab&quot;, we choose the lexicographically smaller substring, which is &quot;ab&quot;. - For the string &quot;ad&quot;, there is no substring that does not occur in any other string. - For the string &quot;bad&quot;, the shortest substring that does not occur in any other string is &quot;ba&quot;. - For the string &quot;c&quot;, there is no substring that does not occur in any other string. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> arr = [&quot;abc&quot;,&quot;bcd&quot;,&quot;abcd&quot;] <strong>Output:</strong> [&quot;&quot;,&quot;&quot;,&quot;abcd&quot;] <strong>Explanation:</strong> We have the following: - For the string &quot;abc&quot;, there is no substring that does not occur in any other string. - For the string &quot;bcd&quot;, there is no substring that does not occur in any other string. - For the string &quot;abcd&quot;, the shortest substring that does not occur in any other string is &quot;abcd&quot;. </pre> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == arr.length</code></li> <li><code>2 &lt;= n &lt;= 100</code></li> <li><code>1 &lt;= arr[i].length &lt;= 20</code></li> <li><code>arr[i]</code> consists only of lowercase English letters.</li> </ul>
Trie; Array; Hash Table; String
TypeScript
function shortestSubstrings(arr: string[]): string[] { const n: number = arr.length; const ans: string[] = Array(n).fill(''); for (let i = 0; i < n; ++i) { const m: number = arr[i].length; for (let j = 1; j <= m && ans[i] === ''; ++j) { for (let l = 0; l <= m - j; ++l) { const sub: string = arr[i].slice(l, l + j); if (ans[i] === '' || sub.localeCompare(ans[i]) < 0) { let ok: boolean = true; for (let k = 0; k < n && ok; ++k) { if (k !== i && arr[k].includes(sub)) { ok = false; } } if (ok) { ans[i] = sub; } } } } } return ans; }
3,077
Maximum Strength of K Disjoint Subarrays
Hard
<p>You are given an array of integers <code>nums</code> with length <code>n</code>, and a positive <strong>odd</strong> integer <code>k</code>.</p> <p>Select exactly <b><code>k</code></b> disjoint <span data-keyword="subarray-nonempty">subarrays</span> <b><code>sub<sub>1</sub>, sub<sub>2</sub>, ..., sub<sub>k</sub></code></b> from <code>nums</code> such that the last element of <code>sub<sub>i</sub></code> appears before the first element of <code>sub<sub>{i+1}</sub></code> for all <code>1 &lt;= i &lt;= k-1</code>. The goal is to maximize their combined strength.</p> <p>The strength of the selected subarrays is defined as:</p> <p><code>strength = k * sum(sub<sub>1</sub>)- (k - 1) * sum(sub<sub>2</sub>) + (k - 2) * sum(sub<sub>3</sub>) - ... - 2 * sum(sub<sub>{k-1}</sub>) + sum(sub<sub>k</sub>)</code></p> <p>where <b><code>sum(sub<sub>i</sub>)</code></b> is the sum of the elements in the <code>i</code>-th subarray.</p> <p>Return the <strong>maximum</strong> possible strength that can be obtained from selecting exactly <b><code>k</code></b> disjoint subarrays from <code>nums</code>.</p> <p><strong>Note</strong> that the chosen subarrays <strong>don&#39;t</strong> need to cover the entire array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,-1,2], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">22</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 3 subarrays is: nums[0..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 3 * (1 + 2 + 3) - 2 * (-1) + 2 = 22</code></p> <p>&nbsp;</p> <p><strong class="example">Example 2:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [12,-2,-2,-2,-2], k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">64</span></p> <p><strong>Explanation:</strong></p> <p>The only possible way to select 5 disjoint subarrays is: nums[0..0], nums[1..1], nums[2..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 5 * 12 - 4 * (-2) + 3 * (-2) - 2 * (-2) + (-2) = 64</code></p> <p><strong class="example">Example 3:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [-1,-2,-3], k = </span>1</p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 1 subarray is: nums[0..0]. The strength is -1.</p> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10<sup>4</sup></code></li> <li><code>-10<sup>9</sup> &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> <li><code>1 &lt;= n * k &lt;= 10<sup>6</sup></code></li> <li><code>k</code> is odd.</li> </ul>
Array; Dynamic Programming; Prefix Sum
C++
class Solution { public: long long maximumStrength(vector<int>& nums, int k) { int n = nums.size(); long long f[n + 1][k + 1][2]; memset(f, -0x3f3f3f3f3f3f3f3f, sizeof(f)); f[0][0][0] = 0; for (int i = 1; i <= n; i++) { int x = nums[i - 1]; for (int j = 0; j <= k; j++) { long long sign = (j & 1) == 1 ? 1 : -1; long long val = sign * x * (k - j + 1); f[i][j][0] = max(f[i - 1][j][0], f[i - 1][j][1]); f[i][j][1] = max(f[i][j][1], f[i - 1][j][1] + val); if (j > 0) { long long t = max(f[i - 1][j - 1][0], f[i - 1][j - 1][1]) + val; f[i][j][1] = max(f[i][j][1], t); } } } return max(f[n][k][0], f[n][k][1]); } };
3,077
Maximum Strength of K Disjoint Subarrays
Hard
<p>You are given an array of integers <code>nums</code> with length <code>n</code>, and a positive <strong>odd</strong> integer <code>k</code>.</p> <p>Select exactly <b><code>k</code></b> disjoint <span data-keyword="subarray-nonempty">subarrays</span> <b><code>sub<sub>1</sub>, sub<sub>2</sub>, ..., sub<sub>k</sub></code></b> from <code>nums</code> such that the last element of <code>sub<sub>i</sub></code> appears before the first element of <code>sub<sub>{i+1}</sub></code> for all <code>1 &lt;= i &lt;= k-1</code>. The goal is to maximize their combined strength.</p> <p>The strength of the selected subarrays is defined as:</p> <p><code>strength = k * sum(sub<sub>1</sub>)- (k - 1) * sum(sub<sub>2</sub>) + (k - 2) * sum(sub<sub>3</sub>) - ... - 2 * sum(sub<sub>{k-1}</sub>) + sum(sub<sub>k</sub>)</code></p> <p>where <b><code>sum(sub<sub>i</sub>)</code></b> is the sum of the elements in the <code>i</code>-th subarray.</p> <p>Return the <strong>maximum</strong> possible strength that can be obtained from selecting exactly <b><code>k</code></b> disjoint subarrays from <code>nums</code>.</p> <p><strong>Note</strong> that the chosen subarrays <strong>don&#39;t</strong> need to cover the entire array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,-1,2], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">22</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 3 subarrays is: nums[0..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 3 * (1 + 2 + 3) - 2 * (-1) + 2 = 22</code></p> <p>&nbsp;</p> <p><strong class="example">Example 2:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [12,-2,-2,-2,-2], k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">64</span></p> <p><strong>Explanation:</strong></p> <p>The only possible way to select 5 disjoint subarrays is: nums[0..0], nums[1..1], nums[2..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 5 * 12 - 4 * (-2) + 3 * (-2) - 2 * (-2) + (-2) = 64</code></p> <p><strong class="example">Example 3:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [-1,-2,-3], k = </span>1</p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 1 subarray is: nums[0..0]. The strength is -1.</p> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10<sup>4</sup></code></li> <li><code>-10<sup>9</sup> &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> <li><code>1 &lt;= n * k &lt;= 10<sup>6</sup></code></li> <li><code>k</code> is odd.</li> </ul>
Array; Dynamic Programming; Prefix Sum
Go
func maximumStrength(nums []int, k int) int64 { n := len(nums) f := make([][][]int64, n+1) const inf int64 = math.MinInt64 / 2 for i := range f { f[i] = make([][]int64, k+1) for j := range f[i] { f[i][j] = []int64{inf, inf} } } f[0][0][0] = 0 for i := 1; i <= n; i++ { x := nums[i-1] for j := 0; j <= k; j++ { sign := int64(-1) if j&1 == 1 { sign = 1 } val := sign * int64(x) * int64(k-j+1) f[i][j][0] = max(f[i-1][j][0], f[i-1][j][1]) f[i][j][1] = max(f[i][j][1], f[i-1][j][1]+val) if j > 0 { t := max(f[i-1][j-1][0], f[i-1][j-1][1]) + val f[i][j][1] = max(f[i][j][1], t) } } } return max(f[n][k][0], f[n][k][1]) }
3,077
Maximum Strength of K Disjoint Subarrays
Hard
<p>You are given an array of integers <code>nums</code> with length <code>n</code>, and a positive <strong>odd</strong> integer <code>k</code>.</p> <p>Select exactly <b><code>k</code></b> disjoint <span data-keyword="subarray-nonempty">subarrays</span> <b><code>sub<sub>1</sub>, sub<sub>2</sub>, ..., sub<sub>k</sub></code></b> from <code>nums</code> such that the last element of <code>sub<sub>i</sub></code> appears before the first element of <code>sub<sub>{i+1}</sub></code> for all <code>1 &lt;= i &lt;= k-1</code>. The goal is to maximize their combined strength.</p> <p>The strength of the selected subarrays is defined as:</p> <p><code>strength = k * sum(sub<sub>1</sub>)- (k - 1) * sum(sub<sub>2</sub>) + (k - 2) * sum(sub<sub>3</sub>) - ... - 2 * sum(sub<sub>{k-1}</sub>) + sum(sub<sub>k</sub>)</code></p> <p>where <b><code>sum(sub<sub>i</sub>)</code></b> is the sum of the elements in the <code>i</code>-th subarray.</p> <p>Return the <strong>maximum</strong> possible strength that can be obtained from selecting exactly <b><code>k</code></b> disjoint subarrays from <code>nums</code>.</p> <p><strong>Note</strong> that the chosen subarrays <strong>don&#39;t</strong> need to cover the entire array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,-1,2], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">22</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 3 subarrays is: nums[0..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 3 * (1 + 2 + 3) - 2 * (-1) + 2 = 22</code></p> <p>&nbsp;</p> <p><strong class="example">Example 2:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [12,-2,-2,-2,-2], k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">64</span></p> <p><strong>Explanation:</strong></p> <p>The only possible way to select 5 disjoint subarrays is: nums[0..0], nums[1..1], nums[2..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 5 * 12 - 4 * (-2) + 3 * (-2) - 2 * (-2) + (-2) = 64</code></p> <p><strong class="example">Example 3:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [-1,-2,-3], k = </span>1</p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 1 subarray is: nums[0..0]. The strength is -1.</p> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10<sup>4</sup></code></li> <li><code>-10<sup>9</sup> &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> <li><code>1 &lt;= n * k &lt;= 10<sup>6</sup></code></li> <li><code>k</code> is odd.</li> </ul>
Array; Dynamic Programming; Prefix Sum
Java
class Solution { public long maximumStrength(int[] nums, int k) { int n = nums.length; long[][][] f = new long[n + 1][k + 1][2]; for (int i = 0; i <= n; i++) { for (int j = 0; j <= k; j++) { Arrays.fill(f[i][j], Long.MIN_VALUE / 2); } } f[0][0][0] = 0; for (int i = 1; i <= n; i++) { int x = nums[i - 1]; for (int j = 0; j <= k; j++) { long sign = (j & 1) == 1 ? 1 : -1; long val = sign * x * (k - j + 1); f[i][j][0] = Math.max(f[i - 1][j][0], f[i - 1][j][1]); f[i][j][1] = Math.max(f[i][j][1], f[i - 1][j][1] + val); if (j > 0) { long t = Math.max(f[i - 1][j - 1][0], f[i - 1][j - 1][1]) + val; f[i][j][1] = Math.max(f[i][j][1], t); } } } return Math.max(f[n][k][0], f[n][k][1]); } }
3,077
Maximum Strength of K Disjoint Subarrays
Hard
<p>You are given an array of integers <code>nums</code> with length <code>n</code>, and a positive <strong>odd</strong> integer <code>k</code>.</p> <p>Select exactly <b><code>k</code></b> disjoint <span data-keyword="subarray-nonempty">subarrays</span> <b><code>sub<sub>1</sub>, sub<sub>2</sub>, ..., sub<sub>k</sub></code></b> from <code>nums</code> such that the last element of <code>sub<sub>i</sub></code> appears before the first element of <code>sub<sub>{i+1}</sub></code> for all <code>1 &lt;= i &lt;= k-1</code>. The goal is to maximize their combined strength.</p> <p>The strength of the selected subarrays is defined as:</p> <p><code>strength = k * sum(sub<sub>1</sub>)- (k - 1) * sum(sub<sub>2</sub>) + (k - 2) * sum(sub<sub>3</sub>) - ... - 2 * sum(sub<sub>{k-1}</sub>) + sum(sub<sub>k</sub>)</code></p> <p>where <b><code>sum(sub<sub>i</sub>)</code></b> is the sum of the elements in the <code>i</code>-th subarray.</p> <p>Return the <strong>maximum</strong> possible strength that can be obtained from selecting exactly <b><code>k</code></b> disjoint subarrays from <code>nums</code>.</p> <p><strong>Note</strong> that the chosen subarrays <strong>don&#39;t</strong> need to cover the entire array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,-1,2], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">22</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 3 subarrays is: nums[0..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 3 * (1 + 2 + 3) - 2 * (-1) + 2 = 22</code></p> <p>&nbsp;</p> <p><strong class="example">Example 2:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [12,-2,-2,-2,-2], k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">64</span></p> <p><strong>Explanation:</strong></p> <p>The only possible way to select 5 disjoint subarrays is: nums[0..0], nums[1..1], nums[2..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 5 * 12 - 4 * (-2) + 3 * (-2) - 2 * (-2) + (-2) = 64</code></p> <p><strong class="example">Example 3:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [-1,-2,-3], k = </span>1</p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 1 subarray is: nums[0..0]. The strength is -1.</p> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10<sup>4</sup></code></li> <li><code>-10<sup>9</sup> &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> <li><code>1 &lt;= n * k &lt;= 10<sup>6</sup></code></li> <li><code>k</code> is odd.</li> </ul>
Array; Dynamic Programming; Prefix Sum
Python
class Solution: def maximumStrength(self, nums: List[int], k: int) -> int: n = len(nums) f = [[[-inf, -inf] for _ in range(k + 1)] for _ in range(n + 1)] f[0][0][0] = 0 for i, x in enumerate(nums, 1): for j in range(k + 1): sign = 1 if j & 1 else -1 f[i][j][0] = max(f[i - 1][j][0], f[i - 1][j][1]) f[i][j][1] = max(f[i][j][1], f[i - 1][j][1] + sign * x * (k - j + 1)) if j: f[i][j][1] = max( f[i][j][1], max(f[i - 1][j - 1]) + sign * x * (k - j + 1) ) return max(f[n][k])
3,077
Maximum Strength of K Disjoint Subarrays
Hard
<p>You are given an array of integers <code>nums</code> with length <code>n</code>, and a positive <strong>odd</strong> integer <code>k</code>.</p> <p>Select exactly <b><code>k</code></b> disjoint <span data-keyword="subarray-nonempty">subarrays</span> <b><code>sub<sub>1</sub>, sub<sub>2</sub>, ..., sub<sub>k</sub></code></b> from <code>nums</code> such that the last element of <code>sub<sub>i</sub></code> appears before the first element of <code>sub<sub>{i+1}</sub></code> for all <code>1 &lt;= i &lt;= k-1</code>. The goal is to maximize their combined strength.</p> <p>The strength of the selected subarrays is defined as:</p> <p><code>strength = k * sum(sub<sub>1</sub>)- (k - 1) * sum(sub<sub>2</sub>) + (k - 2) * sum(sub<sub>3</sub>) - ... - 2 * sum(sub<sub>{k-1}</sub>) + sum(sub<sub>k</sub>)</code></p> <p>where <b><code>sum(sub<sub>i</sub>)</code></b> is the sum of the elements in the <code>i</code>-th subarray.</p> <p>Return the <strong>maximum</strong> possible strength that can be obtained from selecting exactly <b><code>k</code></b> disjoint subarrays from <code>nums</code>.</p> <p><strong>Note</strong> that the chosen subarrays <strong>don&#39;t</strong> need to cover the entire array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,-1,2], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">22</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 3 subarrays is: nums[0..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 3 * (1 + 2 + 3) - 2 * (-1) + 2 = 22</code></p> <p>&nbsp;</p> <p><strong class="example">Example 2:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [12,-2,-2,-2,-2], k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">64</span></p> <p><strong>Explanation:</strong></p> <p>The only possible way to select 5 disjoint subarrays is: nums[0..0], nums[1..1], nums[2..2], nums[3..3], and nums[4..4]. The strength is calculated as follows:</p> <p><code>strength = 5 * 12 - 4 * (-2) + 3 * (-2) - 2 * (-2) + (-2) = 64</code></p> <p><strong class="example">Example 3:</strong></p> <p><strong>Input:</strong> <span class="example-io">nums = [-1,-2,-3], k = </span>1</p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>The best possible way to select 1 subarray is: nums[0..0]. The strength is -1.</p> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10<sup>4</sup></code></li> <li><code>-10<sup>9</sup> &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> <li><code>1 &lt;= n * k &lt;= 10<sup>6</sup></code></li> <li><code>k</code> is odd.</li> </ul>
Array; Dynamic Programming; Prefix Sum
TypeScript
function maximumStrength(nums: number[], k: number): number { const n: number = nums.length; const f: number[][][] = Array.from({ length: n + 1 }, () => Array.from({ length: k + 1 }, () => [-Infinity, -Infinity]), ); f[0][0][0] = 0; for (let i = 1; i <= n; i++) { const x: number = nums[i - 1]; for (let j = 0; j <= k; j++) { const sign: number = (j & 1) === 1 ? 1 : -1; const val: number = sign * x * (k - j + 1); f[i][j][0] = Math.max(f[i - 1][j][0], f[i - 1][j][1]); f[i][j][1] = Math.max(f[i][j][1], f[i - 1][j][1] + val); if (j > 0) { f[i][j][1] = Math.max(f[i][j][1], Math.max(...f[i - 1][j - 1]) + val); } } } return Math.max(...f[n][k]); }
3,078
Match Alphanumerical Pattern in Matrix I
Medium
<p>You are given a 2D integer matrix <code>board</code> and a 2D character matrix <code>pattern</code>. Where <code>0 &lt;= board[r][c] &lt;= 9</code> and each element of <code>pattern</code> is either a digit or a lowercase English letter.</p> <p>Your task is to find a <span data-keyword="submatrix">submatrix</span> of <code>board</code> that <strong>matches</strong> <code>pattern</code>.</p> <p>An integer matrix <code>part</code> matches <code>pattern</code> if we can replace cells containing letters in <code>pattern</code> with some digits (each <strong>distinct</strong> letter with a <strong>unique</strong> digit) in such a way that the resulting matrix becomes identical to the integer matrix <code>part</code>. In other words,</p> <ul> <li>The matrices have identical dimensions.</li> <li>If <code>pattern[r][c]</code> is a digit, then <code>part[r][c]</code> must be the <strong>same</strong> digit.</li> <li>If <code>pattern[r][c]</code> is a letter <code>x</code>: <ul> <li>For every <code>pattern[i][j] == x</code>, <code>part[i][j]</code> must be the <strong>same</strong> as <code>part[r][c]</code>.</li> <li>For every <code>pattern[i][j] != x</code>, <code>part[i][j]</code> must be <strong>different</strong> than <code>part[r][c]</code>.<span style="display: none;"> </span></li> </ul> </li> </ul> <p>Return <em>an array of length </em><code>2</code><em> containing the row number and column number of the upper-left corner of a submatrix of </em><code>board</code><em> which matches </em><code>pattern</code><em>. If there is more than one such submatrix, return the coordinates of the submatrix with the lowest row index, and in case there is still a tie, return the coordinates of the submatrix with the lowest column index. If there are no suitable answers, return</em> <code>[-1, -1]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div style="display:flex; flex-wrap: wrap; align-items: flex-start; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">2</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">a</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> </tr> </tbody> </table> </div> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">board = [[1,2,2],[2,2,3],[2,3,3]], pattern = [&quot;ab&quot;,&quot;bb&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,0]</span></p> <p><strong>Explanation:</strong> If we consider this mapping: <code>&quot;a&quot; -&gt; 1</code> and <code>&quot;b&quot; -&gt; 2</code>; the submatrix with the upper-left corner <code>(0,0)</code> is a match as outlined in the matrix above.</p> <p>Note that the submatrix with the upper-left corner (1,1) is also a match but since it comes after the other one, we return <code>[0,0]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div style="display:flex; flex-wrap: wrap; align-items: flex-start; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">3</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">4</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">6</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">6</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">a</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> </tr> </tbody> </table> </div> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">board = [[1,1,2],[3,3,4],[6,6,6]], pattern = [&quot;ab&quot;,&quot;66&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,1]</span></p> <p><strong>Explanation:</strong> If we consider this mapping: <code>&quot;a&quot; -&gt; 3</code> and <code>&quot;b&quot; -&gt; 4</code>; the submatrix with the upper-left corner <code>(1,1)</code> is a match as outlined in the matrix above.</p> <p>Note that since the corresponding values of <code>&quot;a&quot;</code> and <code>&quot;b&quot;</code> must differ, the submatrix with the upper-left corner <code>(1,0)</code> is not a match. Hence, we return <code>[1,1]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div style="display:flex; flex-wrap: wrap; align-items: flex-start; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">x</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">x</td> </tr> </tbody> </table> </div> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">board = [[1,2],[2,1]], pattern = [&quot;xx&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> <p><strong>Explanation:</strong> Since the values of the matched submatrix must be the same, there is no match. Hence, we return <code>[-1,-1]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= board.length &lt;= 50</code></li> <li><code>1 &lt;= board[i].length &lt;= 50</code></li> <li><code>0 &lt;= board[i][j] &lt;= 9</code></li> <li><code>1 &lt;= pattern.length &lt;= 50</code></li> <li><code>1 &lt;= pattern[i].length &lt;= 50</code></li> <li><code>pattern[i][j]</code> is either a digit represented as a string or a lowercase English letter.</li> </ul>
Array; Hash Table; String; Matrix
C++
class Solution { public: vector<int> findPattern(vector<vector<int>>& board, vector<string>& pattern) { int m = board.size(), n = board[0].size(); int r = pattern.size(), c = pattern[0].size(); auto check = [&](int i, int j) { vector<int> d1(26, -1); vector<int> d2(10, -1); for (int a = 0; a < r; ++a) { for (int b = 0; b < c; ++b) { int x = i + a, y = j + b; if (isdigit(pattern[a][b])) { int v = pattern[a][b] - '0'; if (v != board[x][y]) { return false; } } else { int v = pattern[a][b] - 'a'; if (d1[v] != -1 && d1[v] != board[x][y]) { return false; } if (d2[board[x][y]] != -1 && d2[board[x][y]] != v) { return false; } d1[v] = board[x][y]; d2[board[x][y]] = v; } } } return true; }; for (int i = 0; i < m - r + 1; ++i) { for (int j = 0; j < n - c + 1; ++j) { if (check(i, j)) { return {i, j}; } } } return {-1, -1}; } };
3,078
Match Alphanumerical Pattern in Matrix I
Medium
<p>You are given a 2D integer matrix <code>board</code> and a 2D character matrix <code>pattern</code>. Where <code>0 &lt;= board[r][c] &lt;= 9</code> and each element of <code>pattern</code> is either a digit or a lowercase English letter.</p> <p>Your task is to find a <span data-keyword="submatrix">submatrix</span> of <code>board</code> that <strong>matches</strong> <code>pattern</code>.</p> <p>An integer matrix <code>part</code> matches <code>pattern</code> if we can replace cells containing letters in <code>pattern</code> with some digits (each <strong>distinct</strong> letter with a <strong>unique</strong> digit) in such a way that the resulting matrix becomes identical to the integer matrix <code>part</code>. In other words,</p> <ul> <li>The matrices have identical dimensions.</li> <li>If <code>pattern[r][c]</code> is a digit, then <code>part[r][c]</code> must be the <strong>same</strong> digit.</li> <li>If <code>pattern[r][c]</code> is a letter <code>x</code>: <ul> <li>For every <code>pattern[i][j] == x</code>, <code>part[i][j]</code> must be the <strong>same</strong> as <code>part[r][c]</code>.</li> <li>For every <code>pattern[i][j] != x</code>, <code>part[i][j]</code> must be <strong>different</strong> than <code>part[r][c]</code>.<span style="display: none;"> </span></li> </ul> </li> </ul> <p>Return <em>an array of length </em><code>2</code><em> containing the row number and column number of the upper-left corner of a submatrix of </em><code>board</code><em> which matches </em><code>pattern</code><em>. If there is more than one such submatrix, return the coordinates of the submatrix with the lowest row index, and in case there is still a tie, return the coordinates of the submatrix with the lowest column index. If there are no suitable answers, return</em> <code>[-1, -1]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div style="display:flex; flex-wrap: wrap; align-items: flex-start; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">2</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">a</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> </tr> </tbody> </table> </div> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">board = [[1,2,2],[2,2,3],[2,3,3]], pattern = [&quot;ab&quot;,&quot;bb&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,0]</span></p> <p><strong>Explanation:</strong> If we consider this mapping: <code>&quot;a&quot; -&gt; 1</code> and <code>&quot;b&quot; -&gt; 2</code>; the submatrix with the upper-left corner <code>(0,0)</code> is a match as outlined in the matrix above.</p> <p>Note that the submatrix with the upper-left corner (1,1) is also a match but since it comes after the other one, we return <code>[0,0]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div style="display:flex; flex-wrap: wrap; align-items: flex-start; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">3</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">4</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">6</td> <td style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">6</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">a</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">b</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> </tr> </tbody> </table> </div> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">board = [[1,1,2],[3,3,4],[6,6,6]], pattern = [&quot;ab&quot;,&quot;66&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,1]</span></p> <p><strong>Explanation:</strong> If we consider this mapping: <code>&quot;a&quot; -&gt; 3</code> and <code>&quot;b&quot; -&gt; 4</code>; the submatrix with the upper-left corner <code>(1,1)</code> is a match as outlined in the matrix above.</p> <p>Note that since the corresponding values of <code>&quot;a&quot;</code> and <code>&quot;b&quot;</code> must differ, the submatrix with the upper-left corner <code>(1,0)</code> is not a match. Hence, we return <code>[1,1]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div style="display:flex; flex-wrap: wrap; align-items: flex-start; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">x</td> <td style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">x</td> </tr> </tbody> </table> </div> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">board = [[1,2],[2,1]], pattern = [&quot;xx&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> <p><strong>Explanation:</strong> Since the values of the matched submatrix must be the same, there is no match. Hence, we return <code>[-1,-1]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= board.length &lt;= 50</code></li> <li><code>1 &lt;= board[i].length &lt;= 50</code></li> <li><code>0 &lt;= board[i][j] &lt;= 9</code></li> <li><code>1 &lt;= pattern.length &lt;= 50</code></li> <li><code>1 &lt;= pattern[i].length &lt;= 50</code></li> <li><code>pattern[i][j]</code> is either a digit represented as a string or a lowercase English letter.</li> </ul>
Array; Hash Table; String; Matrix
Go
func findPattern(board [][]int, pattern []string) []int { m, n := len(board), len(board[0]) r, c := len(pattern), len(pattern[0]) check := func(i, j int) bool { d1 := [26]int{} d2 := [10]int{} for a := 0; a < r; a++ { for b := 0; b < c; b++ { x, y := i+a, j+b if pattern[a][b] >= '0' && pattern[a][b] <= '9' { v := int(pattern[a][b] - '0') if v != board[x][y] { return false } } else { v := int(pattern[a][b] - 'a') if d1[v] > 0 && d1[v]-1 != board[x][y] { return false } if d2[board[x][y]] > 0 && d2[board[x][y]]-1 != v { return false } d1[v] = board[x][y] + 1 d2[board[x][y]] = v + 1 } } } return true } for i := 0; i < m-r+1; i++ { for j := 0; j < n-c+1; j++ { if check(i, j) { return []int{i, j} } } } return []int{-1, -1} }