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construct-the-minimum-bitwise-array-i
C# Linq 1 line
c-linq-1-line-by-gbamqzkdyg-xgij
Complexity\n- Time complexity:\nO(n)\n\n- Space complexity:\nO(n)\n\n# Code\ncsharp []\npublic class Solution {\n public int[] MinBitwiseArray(IList<int> num
gbamqzkdyg
NORMAL
2024-10-14T08:13:32.961343+00:00
2024-10-14T08:13:32.961377+00:00
7
false
# Complexity\n- Time complexity:\n$$O(n)$$\n\n- Space complexity:\n$$O(n)$$\n\n# Code\n```csharp []\npublic class Solution {\n public int[] MinBitwiseArray(IList<int> nums) => nums.Select(num => num % 2 == 0 ? -1 : num - ((num + 1) & (-num - 1)) / 2).ToArray();\n}\n```
0
0
['C#']
0
construct-the-minimum-bitwise-array-i
brute force
brute-force-by-user5285zn-jiuu
\nrust []\nfn f(x: i32) -> i32 {\n for y in 1..x {\n if (y | (y+1)) as i32 == x {return y}\n }\n -1\n}\nimpl Solution {\n pub fn min_bitwise
user5285Zn
NORMAL
2024-10-14T04:56:38.174853+00:00
2024-10-14T04:56:38.174888+00:00
1
false
\n```rust []\nfn f(x: i32) -> i32 {\n for y in 1..x {\n if (y | (y+1)) as i32 == x {return y}\n }\n -1\n}\nimpl Solution {\n pub fn min_bitwise_array(nums: Vec<i32>) -> Vec<i32> {\n nums.into_iter().map(f).collect()\n }\n}\n```
0
0
['Rust']
0
construct-the-minimum-bitwise-array-i
Min Bitwise Array - JS
min-bitwise-array-js-by-zemamba-g5ft
javascript []\n/**\n * @param {number[]} nums\n * @return {number[]}\n */\nvar minBitwiseArray = function(nums) {\n ans = []\n for (let i = 0; i < nums.le
zemamba
NORMAL
2024-10-13T20:29:29.510840+00:00
2024-10-13T20:29:29.510867+00:00
5
false
```javascript []\n/**\n * @param {number[]} nums\n * @return {number[]}\n */\nvar minBitwiseArray = function(nums) {\n ans = []\n for (let i = 0; i < nums.length; i++) {\n for (let j = 1; j < nums[i]; j++) {\n if ((j | (j + 1)) == nums[i]) {\n ans.push(j)\n break\n ...
0
0
['JavaScript']
0
construct-the-minimum-bitwise-array-i
See the python solution
see-the-python-solution-by-testcasefail-cg2p
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
TestCaseFail
NORMAL
2024-10-13T18:25:11.429933+00:00
2024-10-13T18:25:11.429953+00:00
5
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['Python3']
0
construct-the-minimum-bitwise-array-i
C++ Solution
c-solution-by-user1122v-2dv8
\n# Code\ncpp []\nclass Solution {\npublic:\n vector<int> minBitwiseArray(vector<int>& nums) {\n for(int i = 0; i < nums.size(); i++){\n in
user1122v
NORMAL
2024-10-13T17:56:40.686586+00:00
2024-10-13T17:56:40.686628+00:00
9
false
\n# Code\n```cpp []\nclass Solution {\npublic:\n vector<int> minBitwiseArray(vector<int>& nums) {\n for(int i = 0; i < nums.size(); i++){\n int flag = 0;\n for(int j = 1; j < nums[i]; j++){\n if((j | (j + 1)) == nums[i]){\n nums[i] = j;\n ...
0
0
['C++']
0
valid-permutations-for-di-sequence
[C++/Java/Python] DP Solution O(N^2)
cjavapython-dp-solution-on2-by-lee215-gmg2
Intuition\ndp[i][j] means the number of possible permutations of first i + 1 digits,\nwhere the i + 1th digit is j + 1th smallest in the rest of unused digits.\
lee215
NORMAL
2018-09-09T03:11:12.918248+00:00
2020-01-31T07:54:49.540221+00:00
19,948
false
# Intuition\n`dp[i][j]` means the number of possible permutations of first `i + 1` digits,\nwhere the `i + 1`th digit is `j + 1`th smallest in the rest of unused digits.\n\n\nOk, may not make sense ... Let\'s see the following diagram.\n![image](https://s3-lc-upload.s3.amazonaws.com/users/lee215/image_1536486527.png)\n...
288
9
[]
49
valid-permutations-for-di-sequence
Easy-to-understand solution with detailed explanation
easy-to-understand-solution-with-detaile-jmb5
\nBefore diving into the state transition function, let us first start with a simple example.\n\n### 1. a simple example\n\nIn the following discussion, for sim
wxd_sjtu
NORMAL
2018-11-23T07:57:21.259281+00:00
2018-11-23T07:57:21.259326+00:00
7,633
false
\nBefore diving into the state transition function, let us first start with a simple example.\n\n### 1. a simple example\n\nIn the following discussion, for simplification, I will use both notation DI-seq and DI-rule instead of DI sequence.\n\nConsider a permutation 1032, which is based on a DI-seq "DID", how to use it...
164
2
[]
19
valid-permutations-for-di-sequence
Top-down with Memo -> Bottom-up DP -> N^3 DP -> N^2 DP -> O(N) space
top-down-with-memo-bottom-up-dp-n3-dp-n2-f8t1
Top-down with Memo:\n\nDefinition: helper(String s, Map<String, Long> map): Answer to s.\n\nIntuition: Insert the largest number into appropriate postion.\n\neg
wangzi6147
NORMAL
2018-09-09T22:02:54.189890+00:00
2018-10-18T02:01:41.061592+00:00
5,593
false
**Top-down with Memo:**\n\nDefinition: `helper(String s, Map<String, Long> map)`: Answer to `s`.\n\nIntuition: Insert the largest number into appropriate postion.\n\neg. `s=\'IIDD\'`, we can only insert `4` between `I` and `D`. We break the remained numbers `0, 1, 2, 3` into two groups both with the size of 2. We have ...
38
1
[]
6
valid-permutations-for-di-sequence
Share my O(N^3) => O(N^2) C++ DP solution. Including the thoughts of improvement.
share-my-on3-on2-c-dp-solution-including-lsv6
Came up with the original idea during contest, so might not be the best. But it works.\nc++\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n
xidui
NORMAL
2018-09-09T03:20:21.534047+00:00
2018-10-17T13:58:10.604683+00:00
3,498
false
Came up with the original idea during contest, so might not be the best. But it works.\n```c++\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n int N = S.length() + 1;\n int MOD = 1e9 + 7;\n // dp[i][j] number of permutation whose length is i and end with j\n int dp[202][...
25
1
[]
6
valid-permutations-for-di-sequence
How to define the DP states (with clear picture explanation)
how-to-define-the-dp-states-with-clear-p-2w5m
When I tried to understand lee215\'s solution, I got stuck. Then I redescribe this process to better understand the whole process. Credits go to lee215. \nThe
liketheflower
NORMAL
2020-07-02T03:46:16.981643+00:00
2021-06-17T18:54:53.931041+00:00
2,190
false
When I tried to understand lee215\'s [solution](https://leetcode.com/problems/valid-permutations-for-di-sequence/discuss/168278/C++JavaPython-DP-Solution-O(N2)), I got stuck. Then I redescribe this process to better understand the whole process. Credits go to lee215. \nThe intuition is: given a string s, results of th...
21
2
[]
4
valid-permutations-for-di-sequence
Python DP approach (+ some Explanation)
python-dp-approach-some-explanation-by-w-1io4
Most of us here are preparing for programming Interviews and those interviews have a threshold of about 45 minutes, and you have to come-up with an approach, wr
wizard_
NORMAL
2020-06-27T06:31:12.855432+00:00
2020-06-27T06:31:12.855480+00:00
888
false
Most of us here are preparing for programming Interviews and those interviews have a threshold of about 45 minutes, and you have to come-up with an approach, write code, and explain. If you spend some time on the discuss section, you will realize there are some awesome solutions, which take you more than an interview-t...
17
1
[]
1
valid-permutations-for-di-sequence
Python O(N^3)/O(N^2) time O(N) space DP solution with clear explanation (no "relative rank" stuff)
python-on3on2-time-on-space-dp-solution-atmk5
Since I didn\'t understand the relative rank stuff, I found this problem to be quite confusing until I saw this thread:\nhttps://leetcode.com/problems/valid-per
wynning
NORMAL
2018-10-27T23:35:39.578844+00:00
2018-10-27T23:35:39.578883+00:00
1,096
false
Since I didn\'t understand the relative rank stuff, I found this problem to be quite confusing until I saw this thread:\nhttps://leetcode.com/problems/valid-permutations-for-di-sequence/discuss/169126/Visualization-Key-to-the-DP-solution:-imagine-cutting-a-piece-of-paper-and-separating-the-halves\n\n**Property: If we i...
10
1
[]
2
valid-permutations-for-di-sequence
Why Backtracking + Memoization is working ??
why-backtracking-memoization-is-working-ac2j0
To all Coders of the Leetcode Community this post needs to be addressed \nwhy this solution is working ??\n```\nclass Solution {\npublic:\n \n int mod = 1
njcoder
NORMAL
2022-07-06T14:04:29.998988+00:00
2022-07-06T14:04:50.661159+00:00
889
false
To all Coders of the Leetcode Community this post needs to be addressed \nwhy this solution is working ??\n```\nclass Solution {\npublic:\n \n int mod = 1e9 + 7;\n \n int n;\n \n vector<int> vis;\n \n int dp[202][202];\n \n long long func(int i,int j,string &s){\n if(i == n) return ...
9
1
[]
1
valid-permutations-for-di-sequence
C++ | Memoization | Backtracking | Easy
c-memoization-backtracking-easy-by-vaibh-qv4e
\nclass Solution {\npublic:\n int vis[201];\n long long int dp[202][202];\n int mod=1000000007;\n int util(string &s,int index,int prev){\n i
vaibhavagrwal
NORMAL
2021-06-20T17:04:28.950693+00:00
2021-06-20T17:04:28.950739+00:00
1,437
false
```\nclass Solution {\npublic:\n int vis[201];\n long long int dp[202][202];\n int mod=1000000007;\n int util(string &s,int index,int prev){\n if(index==s.size()) return 1;\n \n if(dp[index][prev]!=-1) return dp[index][prev];\n \n long long int cnt=0;\n if(s[index]=...
7
0
['Dynamic Programming', 'Backtracking', 'Memoization', 'C']
3
valid-permutations-for-di-sequence
C++ Soln || BackTracking + DP
c-soln-backtracking-dp-by-mitedyna-mo08
\n#define mod 1000000007;\nclass Solution {\npublic:\n vector<int> vis;\n int dp[201][202];\n int sol(string &s, int ind, int prev){\n if(ind==s
mitedyna
NORMAL
2021-06-04T21:54:43.898302+00:00
2021-06-04T21:54:43.898341+00:00
949
false
```\n#define mod 1000000007;\nclass Solution {\npublic:\n vector<int> vis;\n int dp[201][202];\n int sol(string &s, int ind, int prev){\n if(ind==s.length()+1){return 1;}\n if(dp[ind][prev+1]!=-1)return dp[ind][prev+1];\n long ans=0;\n for(int i=0;i<=s.length();i++){\n if...
6
1
['Dynamic Programming', 'Backtracking', 'C']
2
valid-permutations-for-di-sequence
DP O(N^2), Space O(N), With intuitive walkthrough about how to derive it.
dp-on2-space-on-with-intuitive-walkthrou-tkaa
Knowing that we only have to figure out how many permutaitons there are, I stopped thinking about index orders, and instead thought about paths.\n\nConceptually
johnb003
NORMAL
2020-10-04T04:51:45.745883+00:00
2020-10-04T04:51:45.745957+00:00
689
false
Knowing that we only have to figure out how many permutaitons there are, I stopped thinking about index orders, and instead thought about paths.\n\nConceptually, with D alone there\'s only one path.\n\n```\n * \n \\\n * (ending)\n ```\n \n If we do DI, then the up path can end either between the existing two nodes...
6
1
[]
0
valid-permutations-for-di-sequence
Java DFS with memo
java-dfs-with-memo-by-mostlyjoking-thyy
\n\nclass Solution {\n private static int MOD = 1000000007;\n public int numPermsDISequence(String S) {\n int res = 0;\n Integer[][] dp = ne
mostlyjoking
NORMAL
2020-05-25T20:03:00.952317+00:00
2020-05-25T20:03:00.952374+00:00
804
false
\n```\nclass Solution {\n private static int MOD = 1000000007;\n public int numPermsDISequence(String S) {\n int res = 0;\n Integer[][] dp = new Integer[S.length() + 1][S.length() + 1];\n \n for (int i = 0; i <= S.length(); i++) {\n res += dfs(i, S.length() - i, dp, S, 0);\n...
5
0
[]
3
valid-permutations-for-di-sequence
Java sol
java-sol-by-cuny-66brother-8i9i
\nclass Solution {\n int mod=1000000007;\n long dp[][];\n public int numPermsDISequence(String s) {//i: string index end: end with number end\n
CUNY-66brother
NORMAL
2020-05-01T11:46:30.108331+00:00
2020-05-01T11:46:30.108365+00:00
625
false
```\nclass Solution {\n int mod=1000000007;\n long dp[][];\n public int numPermsDISequence(String s) {//i: string index end: end with number end\n int len=s.length();\n long res=0;\n dp=new long[len+1][len+1];\n dp[0][0]=1;\n for(int i=1;i<=s.length();i++){\n cha...
4
0
[]
0
valid-permutations-for-di-sequence
Backtracking to DP Java Solution
backtracking-to-dp-java-solution-by-nave-0fw0
Idea\nWe will try all possibilities for all positions and backtracking when we can\'t go further. seen maintains the visited numbers in per recursion tree branc
naveen_kothamasu
NORMAL
2019-05-10T01:11:45.153681+00:00
2019-05-10T01:16:08.057815+00:00
745
false
**Idea**\nWe will try all possibilities for all positions and backtracking when we can\'t go further. `seen` maintains the visited numbers in per recursion tree branch.\n\n**Solution1** **TLE**\n```\nclass Solution {\n int[] seen = null;\n public int numPermsDISequence(String s) {\n seen = new int[s.length...
4
0
[]
1
valid-permutations-for-di-sequence
Backtracking+memoization is working . Why??
backtrackingmemoization-is-working-why-b-9hjf
Doubt\n Since to decide a unique state , we need:\n\n 1.index at which we are currently in string s\n 2.previous element chosen\n
anupamraZ
NORMAL
2023-04-08T04:56:30.258408+00:00
2023-04-08T04:56:30.258438+00:00
302
false
# Doubt\n Since to decide a unique state , we need:\n\n 1.index at which we are currently in string s\n 2.previous element chosen\n 3.set of numbers that are used or left.Here vis vector.\n\n But i have done memoization over first two, but the soln is working.Can\'t understand why??...
3
0
['Backtracking', 'Memoization', 'C++']
0
valid-permutations-for-di-sequence
MEMO/C++
memoc-by-anurag852001-3ew7
\tclass Solution {\n\tpublic:\n int dp[201][201];\n int mod=1e9+7;\n int util(string &s,vector&visited,int curr,int index,int n){\n if(index==s.
anurag852001
NORMAL
2022-06-15T10:24:04.288640+00:00
2022-06-15T10:24:04.288686+00:00
794
false
\tclass Solution {\n\tpublic:\n int dp[201][201];\n int mod=1e9+7;\n int util(string &s,vector<int>&visited,int curr,int index,int n){\n if(index==s.length())\n return 1;\n if(dp[curr][index]!=-1)\n return dp[curr][index];\n int res=0;\n visited[curr]=true;\n ...
3
0
['Dynamic Programming']
1
valid-permutations-for-di-sequence
Detailed explanation and intuition
detailed-explanation-and-intuition-by-se-4a7p
Intuition\n\nThe possible lengths of s, and the fact that there\'s a modulo involved, hints that were dealing with some sort of recursive function.\n\nIndeed, w
sebnyberg
NORMAL
2022-11-05T14:51:59.733483+00:00
2022-11-05T15:03:13.975716+00:00
429
false
# Intuition\n\nThe possible lengths of `s`, and the fact that there\'s a modulo involved, hints that were dealing with some sort of recursive function.\n\nIndeed, we have a very large number of alternatives for each step. For a 200 character string, there are 200 valid first choices to explore (some of which may later ...
2
0
['Go']
0
valid-permutations-for-di-sequence
Python|DP|10 lines of code| Detailed comments
pythondp10-lines-of-code-detailed-commen-q6qd
```\ndef numPermsDISequence(self, s: str) -> int:\n n = len(s)\n \n # len(dp) is the length of remaining unused set as remain_set\n
user5318zb
NORMAL
2022-05-12T04:29:20.046687+00:00
2022-05-12T04:29:20.046727+00:00
528
false
```\ndef numPermsDISequence(self, s: str) -> int:\n n = len(s)\n \n # len(dp) is the length of remaining unused set as remain_set\n # dp[i] means the last digit of any permutation formed by used set is remain_set[i]\n # so, initially, remain_set = [0, 1, ..,n]\n # dp[i] = 1\n ...
2
0
[]
0
valid-permutations-for-di-sequence
C++ | DFS + MEMO
c-dfs-memo-by-kumarabhi98-v0se
\nclass Solution {\npublic:\n int mod = 1e9+7;\n int dfs(vector<vector<int>> &dp,vector<bool> &vis,string &s,int in,int n,int last){\n if(in>=s.siz
kumarabhi98
NORMAL
2022-03-24T17:11:27.424880+00:00
2022-03-24T17:11:27.424923+00:00
575
false
```\nclass Solution {\npublic:\n int mod = 1e9+7;\n int dfs(vector<vector<int>> &dp,vector<bool> &vis,string &s,int in,int n,int last){\n if(in>=s.size()) return 1;\n if(dp[in][last]!=-1) return dp[in][last];\n if(s[in]==\'D\'){ \n long re = 0;\n for(int i = 0; i<last; ...
2
0
['Dynamic Programming', 'C']
1
valid-permutations-for-di-sequence
Python3 divide and conquer solution, slightly quicker than official divide and conquer solution
python3-divide-and-conquer-solution-slig-apg8
\nfrom functools import lru_cache\n\n\nclass Solution:\n def __init__(self):\n self.mod = 10 ** 9 + 7\n\n @lru_cache(maxsize=None)\n def nCk(sel
cava
NORMAL
2019-12-04T07:19:37.417556+00:00
2019-12-04T07:19:37.417595+00:00
432
false
```\nfrom functools import lru_cache\n\n\nclass Solution:\n def __init__(self):\n self.mod = 10 ** 9 + 7\n\n @lru_cache(maxsize=None)\n def nCk(self, n, k):\n if k == 1: return n\n if k == 0 or n == k: return 1\n return self.nCk(n - 1, k - 1) + self.nCk(n - 1, k)\n\n @lru_cache(m...
2
2
['Divide and Conquer', 'Python3']
1
valid-permutations-for-di-sequence
Python recursive solution(Time out and just for reference)
python-recursive-solutiontime-out-and-ju-gq2j
\nclass Solution(object):\n def numPermsDISequence(self, S):\n """\n :type S: str\n :rtype: int\n """\n n = len(S)\n
cslzy
NORMAL
2018-09-09T09:46:46.356936+00:00
2018-10-18T02:34:32.677979+00:00
335
false
```\nclass Solution(object):\n def numPermsDISequence(self, S):\n """\n :type S: str\n :rtype: int\n """\n n = len(S)\n \n def helper(S, D, I):\n if S == \'\': return 1\n sign = S[0]\n S = S[1:]\n \n count = 0\n ...
2
3
[]
0
valid-permutations-for-di-sequence
C++ || Bactracking || Memoization
c-bactracking-memoization-by-akash92-5blh
Intuition\n Describe your first thoughts on how to solve this problem. \nWe need to explore all possible combinations to get the total count of valid permutatio
akash92
NORMAL
2024-09-16T10:34:30.451733+00:00
2024-09-16T10:34:30.451756+00:00
246
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\nWe need to explore all possible combinations to get the total count of valid permutations\nFor this we only need previous element and current index to decide current element\n\n# Complexity\n- Time complexity: $$O(n^3)$$\n<!-- Add your ti...
1
0
['C++']
0
valid-permutations-for-di-sequence
✅Easiest Approach || RECURSIVE -> MEMOIZATION || Jai Shree Ram🚩🚩
easiest-approach-recursive-memoization-j-8ylo
Approach and Intuition\n- Visualising all the possible permuations and returning only valid ones\n- Taking a prev value which checks the prev value taken , now
vermayugam_29
NORMAL
2024-04-28T19:38:35.017352+00:00
2024-04-28T19:38:35.017372+00:00
236
false
# Approach and Intuition\n- Visualising all the possible permuations and returning only valid ones\n- Taking a prev value which checks the prev value taken , now if prev is -1 this means we can taking any integer .\n- If `s[i] == \'I\'` then we need to take only that element which is not visited yet and is `> than prev...
1
1
['Dynamic Programming', 'Backtracking', 'Recursion', 'Python', 'C++', 'Java', 'Python3']
1
valid-permutations-for-di-sequence
explained why backtrack + memorization working
explained-why-backtrack-memorization-wor-hssz
why it works without explicitly saving the state of the visited array?\n\n\nWhen we backtrack and return from a recursive call, we reset _ visited[curr] to fals
demon_code
NORMAL
2023-09-15T20:38:42.767177+00:00
2023-09-15T20:38:42.767205+00:00
404
false
why it works without explicitly saving the state of the visited array?\n\n\nWhen we backtrack and return from a recursive call, we reset ```_ visited[curr] to false _``` which means that the state of visited is restored to what it was before the recursive call.\n\nThe memoization table dp is used to store and retrieve ...
1
0
['Backtracking', 'Memoization', 'C']
0
valid-permutations-for-di-sequence
Solution
solution-by-deleted_user-btew
C++ []\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n int n = S.length(), mod = 1e9 + 7;\n vector<vector<int>> dp(n + 1,
deleted_user
NORMAL
2023-05-11T22:05:47.224145+00:00
2023-05-11T22:18:32.504069+00:00
267
false
```C++ []\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n int n = S.length(), mod = 1e9 + 7;\n vector<vector<int>> dp(n + 1, vector<int>(n + 1));\n for (int j = 0; j <= n; j++) dp[0][j] = 1;\n for (int i = 0; i < n; i++)\n if (S[i] == \'I\')\n ...
1
1
['C++', 'Java', 'Python3']
0
valid-permutations-for-di-sequence
DP Solution
dp-solution-by-garima1501-3qr2
To add a new character to a sequence we only have to consider the last element-\n\nLets say currently DID sequence is 1032- this can form\n\nDIDI - in cases whe
garima1501
NORMAL
2022-10-02T06:55:30.737862+00:00
2022-10-02T07:01:45.913923+00:00
386
false
To add a new character to a sequence we only have to consider the last element-\n\nLets say currently DID sequence is 1032- this can form\n\nDIDI - in cases where we end with 3,4\nDIDD - in cases where we end with 0,1,2\n\nSo just use the last element value to create a new sequence.\n\n```\nclass Solution:\n def num...
1
0
['Python3']
0
valid-permutations-for-di-sequence
Python solution: tricky question
python-solution-tricky-question-by-huiki-6wb2
\nclass Solution:\n # an implicit DP problem\n # For simplicity, let\'s consider the sequence "D"\n # So we have the sequences [0,1] to permute\n #
huikinglam02
NORMAL
2022-07-25T22:30:33.523858+00:00
2022-07-25T22:31:01.982591+00:00
244
false
```\nclass Solution:\n # an implicit DP problem\n # For simplicity, let\'s consider the sequence "D"\n # So we have the sequences [0,1] to permute\n # The valid permutation is [1,0]\n # Now let\'s go to "DI", we add the number 2\n # and let\'s separate the cases in which the sequence ends with differe...
1
0
[]
0
valid-permutations-for-di-sequence
Beats 100% Other's Solutions
beats-100-others-solutions-by-day_trippe-qzg3
\nclass Solution:\n def numPermsDISequence(self, S: str) -> int:\n dp = [1] * (len(S) + 1)\n for a, b in zip(\'I\' + S, S):\n dp = l
Day_Tripper
NORMAL
2022-07-17T06:54:39.101665+00:00
2022-07-17T06:54:39.101832+00:00
246
false
```\nclass Solution:\n def numPermsDISequence(self, S: str) -> int:\n dp = [1] * (len(S) + 1)\n for a, b in zip(\'I\' + S, S):\n dp = list(itertools.accumulate(dp[:-1] if a == b else dp[-1:0:-1]))\n return dp[0] % (10**9 + 7)\n```
1
0
[]
0
valid-permutations-for-di-sequence
[Python3] top-down dp
python3-top-down-dp-by-ye15-7hl9
\n\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n \n @cache \n def fn(i, x): \n """Return number of valid
ye15
NORMAL
2021-06-09T20:27:53.897620+00:00
2021-06-09T20:27:53.897664+00:00
553
false
\n```\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n \n @cache \n def fn(i, x): \n """Return number of valid permutation given x numbers smaller than previous one."""\n if i == len(s): return 1 \n if s[i] == "D": \n if x == 0: re...
1
0
['Python3']
3
valid-permutations-for-di-sequence
Simple C++ solution
simple-c-solution-by-caspar-chen-hku-tnde
\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n int n = S.length(), mod = 1e9 + 7;\n vector<vector<int>> dp(n + 1, vector<in
caspar-chen-hku
NORMAL
2020-05-22T09:43:41.729001+00:00
2020-05-22T09:43:41.729036+00:00
388
false
```\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n int n = S.length(), mod = 1e9 + 7;\n vector<vector<int>> dp(n + 1, vector<int>(n + 1));\n for (int j = 0; j <= n; j++){\n dp[0][j] = 1;\n } \n for (int i = 0; i < n; i++){\n if (S[i] == \'I\...
1
0
[]
2
valid-permutations-for-di-sequence
C++ DP 100%/100%
c-dp-100100-by-tkwind-o8sp
I highly doubt if this is a real interview question or merely from contest, which adopts ideas/techniques in some fields. \n \nThe main challege to apply DP is
tkwind
NORMAL
2020-01-26T00:12:13.521917+00:00
2020-01-26T00:14:24.060978+00:00
405
false
I highly doubt if this is a real interview question or merely from contest, which adopts ideas/techniques in some fields. \n \nThe main challege to apply DP is the state space is too large, if remembering which numbers have been assigned. This challenge can be overcomed by using ranking. For people with background in d...
1
0
[]
2
valid-permutations-for-di-sequence
[JAVA] DFS with memo
java-dfs-with-memo-by-flyflyflyalex-nseo
\'\'\'\n\n\tclass Solution {\n\t\tint MOD = (int)1e9 + 7;\n\t\tpublic int numPermsDISequence(String s) {\n\t\t\tif (s == null || s.length() == 0) {\n\t\t\t\tret
flyflyflyalex
NORMAL
2020-01-16T22:58:10.285566+00:00
2020-01-28T00:26:05.587467+00:00
336
false
\'\'\'\n\n\tclass Solution {\n\t\tint MOD = (int)1e9 + 7;\n\t\tpublic int numPermsDISequence(String s) {\n\t\t\tif (s == null || s.length() == 0) {\n\t\t\t\treturn 0;\n\t\t\t}\n\t\t\tSet<Integer> hashSet = new HashSet<>();\n\t\t\tfor (int i = 0; i <= s.length(); i++) {\n\t\t\t\thashSet.add(i);\n\t\t\t}\n\n\t\t\tlong re...
1
0
[]
0
valid-permutations-for-di-sequence
Java Solution !!!
java-solution-by-kylewzk-f3i9
\n public int numPermsDISequence(String S) {\n int len = S.length(), N = len + 1, mod = 1000000007;\n int[][] dp = new int[N+1][N];\n \n
kylewzk
NORMAL
2019-03-18T05:44:24.123336+00:00
2019-03-18T05:44:24.123384+00:00
556
false
```\n public int numPermsDISequence(String S) {\n int len = S.length(), N = len + 1, mod = 1000000007;\n int[][] dp = new int[N+1][N];\n \n for(int i = 0; i < N; i++) dp[1][i] = 1;\n \n for(int i = 1; i <= len; i++) {\n if(S.charAt(i-1) == \'D\') for(int j = N - i...
1
0
[]
0
valid-permutations-for-di-sequence
10 lines C++, Time O(n^2), Space O(n), with remark
10-lines-c-time-on2-space-on-with-remark-p266
C++\n// K(s, x) = nums of perms with tail ranking x\n// K(s + \'I\') = K(s, x) + K(s, x+1) + ... + K(s, s.len)\n// K(s + \'D\') = K(s, 0) + K(s, 1) + ... + K(s,
pjincz
NORMAL
2018-11-29T08:28:01.202452+00:00
2018-11-29T08:28:01.202511+00:00
450
false
```C++\n// K(s, x) = nums of perms with tail ranking x\n// K(s + \'I\') = K(s, x) + K(s, x+1) + ... + K(s, s.len)\n// K(s + \'D\') = K(s, 0) + K(s, 1) + ... + K(s, x - 1)\n\n// G(s, 0) = 0\n// G(s, x) = K(s, 0) + K(s, 1) + ... + K(s, x - 1)\n\n// K(s + \'I\') = K(s, x) + K(s, x+1) + ... + K(s, s.len) = G(s, s.len + 1) ...
1
1
[]
1
valid-permutations-for-di-sequence
C++ STL partial_sum, 0ms
c-stl-partial_sum-0ms-by-0xffffffff-9bma
class Solution {\n public:\n int numPermsDISequence(string S) {\n int n = S.size() + 1, d = 0, i = 0;\n vector<int> arr(n, 1);\n
0xffffffff
NORMAL
2018-09-09T23:32:58.083920+00:00
2018-09-17T08:21:41.759783+00:00
378
false
class Solution {\n public:\n int numPermsDISequence(string S) {\n int n = S.size() + 1, d = 0, i = 0;\n vector<int> arr(n, 1);\n auto func = [](int a, int b) { return (a + b) % 1000000007; };\n for (char c : S) {\n if (c == \'D\') {\n ...
1
1
[]
1
valid-permutations-for-di-sequence
C++ O(n^2) solution with only one 1D array. Extremely intuitive detailed thought process
c-on2-solution-with-only-one-1d-array-ex-3wje
\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n int MOD = 1e9 + 7;\n deque<int> memo;\n memo.push_back(1);\n f
chenbai10
NORMAL
2018-09-09T06:04:04.474024+00:00
2018-09-09T06:04:04.474078+00:00
519
false
```\nclass Solution {\npublic:\n int numPermsDISequence(string S) {\n int MOD = 1e9 + 7;\n deque<int> memo;\n memo.push_back(1);\n for (int i = 0; i < S.size(); i++) {\n if (S[i] == \'D\') {\n memo.push_back(0);\n for (int j = i; j >= 0; j--) {\n ...
1
1
[]
1
valid-permutations-for-di-sequence
DP, DFS up and down
dp-dfs-up-and-down-by-luudanhhieu-6rjj
Approach n := len(s), up + down + start = n DP dp := make([][]int, n+1) caching for process at index start with up and down is meaning for total greater and les
luudanhhieu
NORMAL
2025-04-04T16:14:58.540682+00:00
2025-04-04T16:14:58.540682+00:00
1
false
# Approach - `n := len(s)`, `up + down + start = n` - DP `dp := make([][]int, n+1)` caching for process at index `start` with `up` and `down` is meaning for total greater and less than number is picking at index `start`. # Complexity - Time complexity:O(n^2) - Space complexity:O(n^2) # Code ```golang [] func numPer...
0
0
['Go']
0
valid-permutations-for-di-sequence
C++ dfs dp memo
c-dp-memo-by-user5976fh-8kpe
null
user5976fh
NORMAL
2025-03-10T00:57:38.451127+00:00
2025-03-10T00:58:22.839421+00:00
8
false
```cpp [] class Solution { public: vector<vector<int>> dp; const int m = 1e9 + 7; string s; int numPermsDISequence(string str) { s = str; int n = s.size(); dp.resize(n, vector<int>(n + 1, -1)); int ans = 0; for (int i = 0; i <= n; ++i){ ans = (ans...
0
0
['C++']
0
valid-permutations-for-di-sequence
Optimizing DI Sequence Permutations: A Python & C++ Dynamic Programming Solution 🚀🔥
optimizing-di-sequence-permutations-a-py-m0od
Intuition 🤔The problem revolves around arranging a permutation of numbers based on D (descending) and I (ascending) constraints. Using dynamic programming, we c
py_rex_47
NORMAL
2025-02-09T13:33:17.837559+00:00
2025-02-09T13:33:17.837559+00:00
11
false
# Intuition 🤔 The problem revolves around arranging a permutation of numbers based on `D` (descending) and `I` (ascending) constraints. Using dynamic programming, we can keep track of valid permutations for each step and build the solution iteratively. # Approach 🛠️ - Use a 2D DP table, where `dp[i][j]` represents t...
0
0
['String', 'Dynamic Programming', 'Python', 'C++', 'Python3']
0
valid-permutations-for-di-sequence
In depth explanation of relative ranking approach (Base case + State transition + Answer) .
in-depth-explanation-of-relative-ranking-dkpg
IntuitionFirstly, let's define the dp state and then understand its meaning in depth . dp[i][j] here represents the number of ways to constuct the permutation u
_rkpro
NORMAL
2025-01-25T04:24:13.556464+00:00
2025-01-25T04:24:13.556464+00:00
9
false
# Intuition <!-- Describe your first thoughts on how to solve this problem. --> Firstly, let's define the $$dp$$ state and then understand its meaning in depth . $$dp[i][j]\ $$here represents the number of ways to constuct the permutation using numbers from $$0$$ to $$i$$ and the $$(i+1)^{th}$$ number of this permutati...
0
0
['C++']
0
valid-permutations-for-di-sequence
DP - All possible permutations
dp-all-possible-permutations-by-vats_lc-mqxd
Code
vats_lc
NORMAL
2025-01-04T13:30:31.666121+00:00
2025-01-04T13:30:31.666121+00:00
8
false
# Code ```cpp [] const int MOD = 1e9 + 7; class Solution { public: int getAns(int i, int n, char ch, int num, string& s, vector<int>& count, vector<vector<int>>& dp) { if (i == n) { for (int j = 0; j <= n; j++) if (count[j] == 1) { if (ch == 'D'...
0
0
['C++']
0
valid-permutations-for-di-sequence
903. Valid Permutations for DI Sequence
903-valid-permutations-for-di-sequence-b-cnlv
IntuitionApproachComplexity Time complexity: Space complexity: Code
G8xd0QPqTy
NORMAL
2025-01-02T02:51:43.906811+00:00
2025-01-02T02:51:43.906811+00:00
5
false
# Intuition <!-- Describe your first thoughts on how to solve this problem. --> # Approach <!-- Describe your approach to solving the problem. --> # Complexity - Time complexity: <!-- Add your time complexity here, e.g. $$O(n)$$ --> - Space complexity: <!-- Add your space complexity here, e.g. $$O(n)$$ --> # Code `...
0
0
['C++']
0
valid-permutations-for-di-sequence
EASY DP || C++ || 👍✅
easy-dp-c-by-athar4403-b1j8
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
Athar4403
NORMAL
2024-10-18T05:10:59.441929+00:00
2024-10-18T05:10:59.441963+00:00
8
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:O(N^3)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:O(N^2)\n<!-- Add your space complexity here, e.g....
0
0
['C++']
0
valid-permutations-for-di-sequence
903. Valid Permutations for DI Sequence.cpp
903-valid-permutations-for-di-sequencecp-5mdt
Code\n\nclass Solution {\npublic:\n int MOD = 1e9+7;\n long long dp[202][202];\n long long perms(string &s, int n, int pos, int prev, vector<bool> &vis
202021ganesh
NORMAL
2024-08-15T12:15:06.906799+00:00
2024-08-15T12:15:06.906831+00:00
4
false
**Code**\n```\nclass Solution {\npublic:\n int MOD = 1e9+7;\n long long dp[202][202];\n long long perms(string &s, int n, int pos, int prev, vector<bool> &visited) {\n if(pos >= n) return 1; \n if(dp[pos][prev] != -1) return dp[pos][prev];\n long long ans = 0;\n for(int i=0;i<=n;i++...
0
0
['C']
0
valid-permutations-for-di-sequence
Dynamic Programming O(n^3) Time Complexity
dynamic-programming-on3-time-complexity-0mxlu
Intuition\n- We can solve this using Dynamic Programming\n- we need to fix valid elements and at the need to check whether we can form a valid permutation or no
yash559
NORMAL
2024-08-15T01:36:32.380919+00:00
2024-08-15T01:36:32.380946+00:00
11
false
# Intuition\n- We can solve this using Dynamic Programming\n- we need to fix valid elements and at the need to check whether we can form a valid permutation or not \n- if we can then add 1 and check for remaining combinations\n\n# Complexity\n- Time complexity: $$O(n^3)$$\n<!-- Add your time complexity here, e.g. $$O(n...
0
0
['C++']
0
valid-permutations-for-di-sequence
help me out please
help-me-out-please-by-lerno_breed-b9ij
\n Describe your first thoughts on how to solve this problem. \n## Why this is not working \n\n\n# Code\n\nclass Solution {\npublic:\n // Brute force\n in
lerno_breed
NORMAL
2024-07-30T10:15:56.356722+00:00
2024-07-30T10:15:56.356757+00:00
5
false
\n<!-- Describe your first thoughts on how to solve this problem. -->\n## Why this is not working \n\n\n# Code\n```\nclass Solution {\npublic:\n // Brute force\n int f(int i, string temp, int prev, string s) {\n int n = s.size();\n if (i == n) {\n \n for (int j = 0; j <= n; j++) {\...
0
0
['C++']
0
valid-permutations-for-di-sequence
Valid Permutation For DI sequence
valid-permutation-for-di-sequence-by-nae-iom0
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
Naeem_ABD
NORMAL
2024-07-16T18:19:14.689998+00:00
2024-07-16T18:19:14.690034+00:00
11
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['Python3']
0
valid-permutations-for-di-sequence
Extremely simple, clear & fast, 20 lines, Runtime: 100%, Memory: 100%, O(n²)
extremely-simple-clear-fast-20-lines-run-r9gq
Intuition & Approach\n Describe your first thoughts on how to solve this problem. \n\nInitially I struggled to find a good solution, calculating permutations is
FSGT
NORMAL
2024-05-28T13:33:16.278833+00:00
2024-05-28T13:47:48.835918+00:00
15
false
# Intuition & Approach\n<!-- Describe your first thoughts on how to solve this problem. -->\n\nInitially I struggled to find a good solution, calculating permutations is very expensive, and with a complicated condition it would be difficult to reuse previously calculated permutations if I also need to keep track of whi...
0
0
['Recursion', 'Memoization', 'C#']
0
valid-permutations-for-di-sequence
Combinatorics Approach 2x+ times faster than DP
combinatorics-approach-2x-times-faster-t-7t3h
Intuition\nFirst, we simplify the input into a series of transitions up and down by some amounts. III becomes a transition with +3 and DDDDD represents one with
jmavis
NORMAL
2024-04-19T23:20:58.119763+00:00
2024-04-22T19:56:55.869807+00:00
9
false
# Intuition\nFirst, we simplify the input into a series of transitions up and down by some amounts. III becomes a transition with +3 and DDDDD represents one with -4. Here is a representation of "DDIIIIDDD" with 3 transition points.\n\n![2.jpg](https://assets.leetcode.com/users/images/503e2c08-cffa-4cff-9574-ec96bf564f...
0
0
['Kotlin']
0
valid-permutations-for-di-sequence
Python recursive solution, detailed explanation
python-recursive-solution-detailed-expla-adux
Intuition\nLooks like a DP problem, since sub problems are getting reused. \n\n# Approach\nWe just need to keep track of state of dp. i.e since we\'re only inte
lostguardian_01
NORMAL
2024-04-16T11:34:02.126842+00:00
2024-04-16T11:34:02.126863+00:00
15
false
# Intuition\nLooks like a DP problem, since sub problems are getting reused. \n\n# Approach\nWe just need to keep track of state of dp. i.e since we\'re only interested in number of solutions, the numbers itself dont matter only the number of elements above and below out previous choice.\n \nState = (idx, u, b) \nidx =...
0
0
['Python3']
0
valid-permutations-for-di-sequence
👍Runtime 598 ms Beats 100.00% of users with Scala
runtime-598-ms-beats-10000-of-users-with-c0zh
Code\n\nobject Solution {\n def numPermsDISequence(s: String): Int = {\n val n = s.length()\n val dp = Array.ofDim[Int](n + 2, 2)\n val
pvt2024
NORMAL
2024-04-11T02:27:42.563647+00:00
2024-04-11T02:27:42.563666+00:00
1
false
# Code\n```\nobject Solution {\n def numPermsDISequence(s: String): Int = {\n val n = s.length()\n val dp = Array.ofDim[Int](n + 2, 2)\n val mod = 1000000007\n dp(1)(0) = 1\n\n for (i <- 1 to n) {\n if (s.charAt(i - 1) == \'I\') {\n for (j <- 0 to i) dp(j ...
0
0
['Scala']
0
valid-permutations-for-di-sequence
Solution Valid Permutations for DI Sequence
solution-valid-permutations-for-di-seque-6wj3
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
Suyono-Sukorame
NORMAL
2024-03-03T13:57:50.479317+00:00
2024-03-03T13:57:50.479345+00:00
3
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['PHP']
0
valid-permutations-for-di-sequence
The constraint is sort of too loose for backtracking to pass
the-constraint-is-sort-of-too-loose-for-3ouxc
Code\n\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n N = len(s)+1\n seen = set([])\n @cache\n def dp(i,prev):
MaxOrgus
NORMAL
2024-02-27T04:15:46.468555+00:00
2024-02-27T04:15:46.468578+00:00
9
false
# Code\n```\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n N = len(s)+1\n seen = set([])\n @cache\n def dp(i,prev):\n if i == N-1:\n return 1\n res = 0\n if prev == -1:\n for k in range(N):\n ...
0
0
['Backtracking', 'Python3']
0
valid-permutations-for-di-sequence
revised_backtrack...
revised_backtrack-by-aman_17000s-flj2
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
aman_17000s
NORMAL
2024-02-24T10:48:51.642920+00:00
2024-02-24T10:48:51.642955+00:00
11
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['Backtracking', 'C++']
0
valid-permutations-for-di-sequence
Dynamic Programming for Permutations with DI Sequence
dynamic-programming-for-permutations-wit-8p1r
Intuition\nThe problem involves finding the number of valid permutations based on a given string s, where \'I\' indicates that the next digit should be greater,
davitacols
NORMAL
2024-02-23T21:38:03.963171+00:00
2024-02-23T21:38:03.963208+00:00
9
false
# Intuition\nThe problem involves finding the number of valid permutations based on a given string `s`, where \'I\' indicates that the next digit should be greater, and \'D\' indicates that the next digit should be smaller. The intuition is to use dynamic programming to build a 2D array `dp` to keep track of the number...
0
0
['Python']
0
valid-permutations-for-di-sequence
Efficient JS solution - DP O(N^2) (Beat 100% time)
efficient-js-solution-dp-on2-beat-100-ti-7xdi
\n\nPro tip: Xi\xE8 \uD83D\uDC9C She\'s really cute tho.\n\n# Complexity\n- Time complexity: O(n^2)\n- Space complexity: O(n)\n\n# Code\njs\nlet MOD = 100000000
CuteTN
NORMAL
2024-01-30T02:33:17.476018+00:00
2024-01-30T02:33:17.476051+00:00
6
false
![image.png](https://assets.leetcode.com/users/images/49843e4a-23a5-4dee-8579-63c97d9f77c9_1706581797.5404885.png)\n\nPro tip: Xi\xE8 \uD83D\uDC9C She\'s really cute tho.\n\n# Complexity\n- Time complexity: $$O(n^2)$$\n- Space complexity: $$O(n)$$\n\n# Code\n```js\nlet MOD = 1000000007;\nlet pre = new Uint32Array(201);...
0
0
['Dynamic Programming', 'JavaScript']
0
valid-permutations-for-di-sequence
✅ C++ Solution DP Memoization ✅
c-solution-dp-memoization-by-atom-1-grrh
\n\n# Code\n\nclass Solution {\npublic:\n int mod = 1e9+7;\n int solve(int i,int ind, string &s,vector<int> &visited,vector<vector<int>> &dp){\n if
atom-1
NORMAL
2024-01-08T13:12:50.506281+00:00
2024-01-08T13:12:50.506318+00:00
76
false
\n\n# Code\n```\nclass Solution {\npublic:\n int mod = 1e9+7;\n int solve(int i,int ind, string &s,vector<int> &visited,vector<vector<int>> &dp){\n if(ind==s.size()) return 1;\n\n if(dp[i][ind]!=-1) return dp[i][ind];\n\n long long int ans = 0;\n if(s[ind]==\'I\'){\n for(...
0
0
['String', 'Dynamic Programming', 'Recursion', 'Memoization', 'C++']
0
valid-permutations-for-di-sequence
python DP top down + backtracking
python-dp-top-down-backtracking-by-harry-nkyl
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
harrychen1995
NORMAL
2023-11-21T16:09:23.367090+00:00
2023-11-21T16:09:23.367120+00:00
20
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['Dynamic Programming', 'Backtracking', 'Python3']
0
valid-permutations-for-di-sequence
Dynamic programming with top to down approach
dynamic-programming-with-top-to-down-app-qiso
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
geeknkta
NORMAL
2023-11-01T06:58:44.300633+00:00
2023-11-01T06:58:44.300659+00:00
19
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['C++']
0
valid-permutations-for-di-sequence
Dynamic programming with top to down approach
dynamic-programming-with-top-to-down-app-5qgp
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
geeknkta
NORMAL
2023-11-01T06:58:43.006844+00:00
2023-11-01T06:58:43.006871+00:00
10
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['C++']
0
valid-permutations-for-di-sequence
java easy memoization after recursion | DP
java-easy-memoization-after-recursion-dp-hrn7
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
vishal_113
NORMAL
2023-10-25T18:53:49.482344+00:00
2023-10-25T18:53:49.482363+00:00
97
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['Dynamic Programming', 'Memoization', 'Java']
0
valid-permutations-for-di-sequence
simple easy to understand c++ solution
simple-easy-to-understand-c-solution-by-n5euk
class Solution {\npublic:\n int numPermsDISequence(string s) {\n constexpr int mod=1\'000\'000\'007;\n int n=s.length();\n vector>DP(n+1
ar2609034
NORMAL
2023-10-17T14:07:23.286734+00:00
2023-10-17T14:07:23.286753+00:00
4
false
class Solution {\npublic:\n int numPermsDISequence(string s) {\n constexpr int mod=1\'000\'000\'007;\n int n=s.length();\n vector<vector<int>>DP(n+1, vector<int>(n+1));\n for(int i=0;i<=n;++i){\n DP[0][i]=1;\n }\n for(int i=1;i<=n;++i){\n if(s[i-1]==\'I...
0
0
[]
0
valid-permutations-for-di-sequence
Easiest Solution
easiest-solution-by-kunal7216-lnpl
\n\n# Code\njava []\nclass Solution {\n public int numPermsDISequence(String s) {\n\tint n = s.length();\n\tint[][] dp = new int [n+2][2];\n\tint mod = 10000
Kunal7216
NORMAL
2023-09-24T15:44:42.358383+00:00
2023-09-24T15:44:42.358405+00:00
68
false
\n\n# Code\n```java []\nclass Solution {\n public int numPermsDISequence(String s) {\n\tint n = s.length();\n\tint[][] dp = new int [n+2][2];\n\tint mod = 1000000007;\n\tdp[1][0] = 1;\n\tfor(int i = 1; i<=n; i++){\n\t\tif(s.charAt(i-1)==\'I\') {\n\t\t\tfor(int j = 0; j<=i; j++) dp[j+1][i&1]=(dp[j][(i+1)&1] + dp[j][i...
0
0
['C++', 'Java']
0
valid-permutations-for-di-sequence
Editorial-like solution, simple to understand with multiple approaches from Brute-force to optimal
editorial-like-solution-simple-to-unders-ee9v
The problem asks what is the number of valid permutations that follow a string of "DI" instructions, if a number i is used in a podition with \'D\' the next num
itaib2004
NORMAL
2023-08-02T09:38:37.534688+00:00
2023-08-02T09:38:37.534710+00:00
52
false
The problem asks what is the number of valid permutations that follow a string of `"DI"` instructions, if a number `i` is used in a podition with `\'D\'` the next number must be in the range `0 <= j < i`, likewise if it\'s in an `\'I\'` position the next number must be `i < j <= n` where `n` is the length if the string...
0
0
['Python3']
0
valid-permutations-for-di-sequence
Simple C++ Solution | Dynamic Programming | Recursion | Memoization
simple-c-solution-dynamic-programming-re-55jb
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
rj_9999
NORMAL
2023-07-07T10:03:50.466912+00:00
2023-07-07T10:03:50.466940+00:00
77
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['Dynamic Programming', 'Recursion', 'Memoization', 'C++']
1
valid-permutations-for-di-sequence
Scala solution
scala-solution-by-malovig-mu9v
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
malovig
NORMAL
2023-06-13T14:55:04.926856+00:00
2023-06-13T14:55:04.926881+00:00
10
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity: O(n^2)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: O(n^2)\n<!-- Add your space complexity here, e....
0
0
['Scala']
0
valid-permutations-for-di-sequence
c++ 3ms dp top down + prefix sum
c-3ms-dp-top-down-prefix-sum-by-vedantna-3sy3
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
vedantnaudiyal
NORMAL
2023-04-29T11:54:37.331369+00:00
2023-04-29T11:54:37.331410+00:00
58
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['C++']
1
valid-permutations-for-di-sequence
O(n^2) DP with O(n) space
on2-dp-with-on-space-by-xjpig-ebf6
Intuition\n Describe your first thoughts on how to solve this problem. \n- dp[j] in the i-th round memorizes the number of permutations ends with j for s[0:i].\
XJPIG
NORMAL
2023-04-26T04:19:42.404935+00:00
2023-04-26T04:19:42.404964+00:00
28
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n- dp[j] in the i-th round memorizes the number of permutations ends with j for s[0:i].\n\n- When s[i] is \'D\', update the ndp[j] with sum(dp[j:i]), which increases each element larger than j by one in the prefix.\n- When s[i] is \'I\', u...
0
0
['C++']
0
valid-permutations-for-di-sequence
Python (Simple DP)
python-simple-dp-by-rnotappl-yy2k
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time
rnotappl
NORMAL
2023-02-25T13:29:51.610198+00:00
2023-02-25T13:29:51.610236+00:00
76
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ --...
0
0
['Python3']
0
valid-permutations-for-di-sequence
C++ Easy Solution✅|Using DP & Backtraking🔥|Optimal Solution
c-easy-solutionusing-dp-backtrakingoptim-8bda
\n\n# Complexity\n- Time complexity:O(NNN)\n\n- Space complexity:O(N*N)\n Add your space complexity here, e.g. O(n) \n\n# Code\n\nclass Solution {\npublic:\n
Jayesh_06
NORMAL
2023-02-18T06:40:56.343790+00:00
2023-02-18T06:40:56.343840+00:00
114
false
\n\n# Complexity\n- Time complexity:O($$N*N*N$$)\n\n- Space complexity:O($$N*N$$)\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass Solution {\npublic:\n int mod=1e9+7;\n //TC=O(N*N*N)\n //SC=O(N*N)\n int find(int ind,int pre,string& s,int n,vector<bool>& vis,vector<vector<int>>&...
0
0
['Dynamic Programming', 'Backtracking', 'Memoization', 'C++']
0
valid-permutations-for-di-sequence
[Scala] Clean Functional DP
scala-clean-functional-dp-by-heavenwatch-qbwr
Let dp[i][j] be the number of permutations that s[i:] could form with the first number be the jth smallest candidate number.\n\nThen if s[i] == \'D\', because f
heavenwatcher
NORMAL
2023-02-13T00:37:55.175611+00:00
2023-02-13T00:40:18.610089+00:00
19
false
Let `dp[i][j]` be the number of permutations that `s[i:]` could form with the first number be the `j`th smallest candidate number.\n\nThen if `s[i] == \'D\'`, because for `dp[i][j]` we already choose the `j`th smallest possible value, we can only choose the candidate numbers before `j` for the `i+1`th position. So `dp[...
0
0
[]
0
valid-permutations-for-di-sequence
Easy C++ Beginner Friendly DP + Backtracking Solution
easy-c-beginner-friendly-dp-backtracking-zbfx
\n\n# Code\n\nclass Solution {\npublic:\n vector<int> vis;\n int dp[202][202];\n int mod = 1000000007;\n int recur(string &s, int i, int n,int idx){
kartikdangi01
NORMAL
2023-01-24T17:36:34.157807+00:00
2023-01-24T17:36:34.157838+00:00
78
false
\n\n# Code\n```\nclass Solution {\npublic:\n vector<int> vis;\n int dp[202][202];\n int mod = 1000000007;\n int recur(string &s, int i, int n,int idx){\n if(idx==n-1){\n return 1;\n }\n if(dp[idx][i]!=-1)\n return dp[idx][i];\n \n int res = 0;\n ...
0
0
['Dynamic Programming', 'Backtracking', 'C++']
0
valid-permutations-for-di-sequence
C solution beats 100%
c-solution-beats-100-by-obose-v1fq
Intuition\n Describe your first thoughts on how to solve this problem. \nThe problem is asking us to find the number of permutations of a string of length n tha
Obose
NORMAL
2023-01-18T03:01:27.390736+00:00
2023-01-18T03:01:27.390773+00:00
51
false
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\nThe problem is asking us to find the number of permutations of a string of length n that satisfy the condition that the string only contains \'I\' and \'D\' and where \'I\' represents increasing and \'D\' represents decreasing.\n\n\n# App...
0
0
['C']
0
valid-permutations-for-di-sequence
Detailed comments for an O(N^2) solution
detailed-comments-for-an-on2-solution-by-czt0
\n# Code\n\nclass Solution {\npublic:\n\n int numPermsDISequence(string s) {\n int N = s.size() + 1;\n vector<vector<int>> dp(N, vector<int>(N)
cal_apple
NORMAL
2023-01-06T08:52:58.617419+00:00
2023-01-06T08:52:58.617454+00:00
55
false
\n# Code\n```\nclass Solution {\npublic:\n\n int numPermsDISequence(string s) {\n int N = s.size() + 1;\n vector<vector<int>> dp(N, vector<int>(N));\n const int mod = 1e9 + 7;\n\n // dp[i][j] : answers for length=i+1 (using number [0,1,..,i]) that ends with j (j <= i)\n for (int j ...
0
0
['C++']
0
valid-permutations-for-di-sequence
Just a runnable solution
just-a-runnable-solution-by-ssrlive-4e9e
Code\n\nimpl Solution {\n pub fn num_perms_di_sequence(s: String) -> i32 {\n let n = s.len();\n let m = 1_000_000_007;\n let mut dp = ve
ssrlive
NORMAL
2023-01-03T07:31:48.025936+00:00
2023-01-03T07:31:48.025976+00:00
26
false
# Code\n```\nimpl Solution {\n pub fn num_perms_di_sequence(s: String) -> i32 {\n let n = s.len();\n let m = 1_000_000_007;\n let mut dp = vec![vec![0; n + 1]; n + 1];\n dp[0][0] = 1;\n for i in 1..=n {\n for j in 0..=i {\n if s.chars().nth(i - 1).unwrap()...
0
0
['Rust']
0
valid-permutations-for-di-sequence
[Python3] | Top-Down DP O(N^2)
python3-top-down-dp-on2-by-swapnilsingh4-03vp
\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n n,ans = len(s),0\n mod = 1_00_00_00_000 + 7\n memo = [[-1] * 201 for
swapnilsingh421
NORMAL
2022-12-16T12:44:38.593003+00:00
2022-12-16T12:44:38.593031+00:00
126
false
```\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n n,ans = len(s),0\n mod = 1_00_00_00_000 + 7\n memo = [[-1] * 201 for i in range(201)]\n def dp(ind,prevNum):\n if ind < 0:\n return 1\n if memo[ind][prevNum] != -1:\n ...
0
0
['Dynamic Programming', 'Python', 'Python3']
0
valid-permutations-for-di-sequence
Python | Backtracking, works and easy to understand
python-backtracking-works-and-easy-to-un-qhda
python\nfrom functools import lru_cache\nclass Solution:\n def numPermsDISequence(self, s):\n return self.backtrack(s) % (10**9 + 7)\n\n def backtr
steve-jokes
NORMAL
2022-11-30T06:50:18.097049+00:00
2022-11-30T06:50:18.097090+00:00
90
false
```python\nfrom functools import lru_cache\nclass Solution:\n def numPermsDISequence(self, s):\n return self.backtrack(s) % (10**9 + 7)\n\n def backtrack(self, s): # with pruning and memo\n L = len(s)\n nums = set(range(-1, L + 1)) # dummy -1 as \'pre\', only happens when idx == 0 (in which...
0
0
['Backtracking', 'Memoization', 'Python']
0
valid-permutations-for-di-sequence
C++ || Backtracking + Memoization
c-backtracking-memoization-by-rohitraj13-seb1
\nclass Solution {\npublic:\n int visited[201];\n int mod = 1e9+7;\n map<pair<int,int>,int>mp;\n int solve(int idx , int last,string &s){\n /
rohitraj13may1998
NORMAL
2022-11-07T16:31:02.168103+00:00
2022-11-07T16:31:02.168145+00:00
119
false
```\nclass Solution {\npublic:\n int visited[201];\n int mod = 1e9+7;\n map<pair<int,int>,int>mp;\n int solve(int idx , int last,string &s){\n //base case\n if(idx<0)return 1;\n \n if(mp.count({idx,last}))\n return mp[{idx,last}];\n int ans = 0 ;\n \n ...
0
0
['Dynamic Programming', 'Backtracking', 'Memoization', 'C++']
0
valid-permutations-for-di-sequence
js solution dp
js-solution-dp-by-renettadonathanrbo95-veuy
\nvar numPermsDISequence = function(s) {\n let mod = 10**9+7,res = 0\n const dp = new Array(s.length+1).fill().map(()=>new Array)\n dp[0][0]=1\n for
renettadonathanrbo95
NORMAL
2022-11-07T08:56:00.549537+00:00
2022-11-07T08:56:00.549584+00:00
39
false
```\nvar numPermsDISequence = function(s) {\n let mod = 10**9+7,res = 0\n const dp = new Array(s.length+1).fill().map(()=>new Array)\n dp[0][0]=1\n for(i=1;i<s.length+1;i++) {\n if(s[i-1]===\'D\') {\n dp[i][i]=0\n for(j=i-1;j>=0;j--) {\n dp[i][j]=(dp[i][j+1]+dp[i-...
0
0
['JavaScript']
0
valid-permutations-for-di-sequence
[C++] Beginner Friendly, DP Solution
c-beginner-friendly-dp-solution-by-hardi-jrgs
\nclass Solution {\npublic:\n int mod=1000000007;\n int solve(string &s, int index, vector<bool> &vis, int last, vector<vector<int> > &dp){\n //if
hardikjain40153
NORMAL
2022-08-22T19:03:35.648661+00:00
2022-08-22T19:03:35.648708+00:00
214
false
```\nclass Solution {\npublic:\n int mod=1000000007;\n int solve(string &s, int index, vector<bool> &vis, int last, vector<vector<int> > &dp){\n //if we reach the last index, there will be single element left we can do this in one way.\n if(index == s.size()){\n return 1;\n }\n ...
0
0
['Dynamic Programming', 'Recursion', 'Memoization', 'C']
0
valid-permutations-for-di-sequence
Java, time O(N^2), space O(N), 3ms=>2ms, dp[n+1]
java-time-on2-space-on-3ms2ms-dpn1-by-vk-7ss1
\npublic int numPermsDISequence(String s) {\n\tint n = s.length();\n\tint[][] dp = new int [n+2][2];\n\tint mod = 1000000007;\n\tdp[1][0] = 1;\n\tfor(int i = 1;
vkochengin
NORMAL
2022-08-19T18:55:26.868210+00:00
2022-08-20T07:51:42.833535+00:00
157
false
```\npublic int numPermsDISequence(String s) {\n\tint n = s.length();\n\tint[][] dp = new int [n+2][2];\n\tint mod = 1000000007;\n\tdp[1][0] = 1;\n\tfor(int i = 1; i<=n; i++){\n\t\tif(s.charAt(i-1)==\'I\') {\n\t\t\tfor(int j = 0; j<=i; j++) dp[j+1][i&1]=(dp[j][(i+1)&1] + dp[j][i&1])%mod; \n\t\t} else {\n\t\t\tfor(int ...
0
0
['Dynamic Programming', 'Java']
0
valid-permutations-for-di-sequence
python3 solution
python3-solution-by-daheofdiamond-zfc5
Solution, requires a bit of observation\n\n\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n myStore = [1]\n \n for ind
daheofdiamond
NORMAL
2022-07-30T00:23:07.200012+00:00
2022-07-30T00:23:07.200049+00:00
177
false
Solution, requires a bit of observation\n\n```\nclass Solution:\n def numPermsDISequence(self, s: str) -> int:\n myStore = [1]\n \n for index, val in enumerate(s):\n if val == 0:\n continue\n temp = []\n for i in range(index + 2):\n ...
0
0
['Python3']
0
valid-permutations-for-di-sequence
JAVA Solution
java-solution-by-user6539fn-mioy
class Solution {\n private static final int mod = 1000000007;\n int[] seen = null;\n Integer[][] dp = null;\n public int numPermsDISequence(String s
user6539fn
NORMAL
2022-07-29T07:26:55.530688+00:00
2022-07-29T07:26:55.530744+00:00
159
false
class Solution {\n private static final int mod = 1000000007;\n int[] seen = null;\n Integer[][] dp = null;\n public int numPermsDISequence(String s) {\n dp = new Integer[s.length()][s.length()+1];\n seen = new int[s.length()+1];\n int count = 0;\n for(int i=0; i <= s.length(); i...
0
0
['Dynamic Programming', 'Memoization', 'Java']
0
valid-permutations-for-di-sequence
ANYONE CAN MODIFY THIS BFS approach with TLE?
anyone-can-modify-this-bfs-approach-with-cwhu
\nclass Solution {\npublic:\n int numPermsDISequence(string s) {\n int n=s.length();\n queue<pair<string,unordered_set<int>>> q;\n unord
Fullmetal_01
NORMAL
2022-07-06T12:47:49.126826+00:00
2022-07-07T05:52:07.527555+00:00
65
false
```\nclass Solution {\npublic:\n int numPermsDISequence(string s) {\n int n=s.length();\n queue<pair<string,unordered_set<int>>> q;\n unordered_set<int> v;\n string str="";\n for(int i=0;i<=n;++i)\n {\n str="";\n v.clear();\n str+=(i+\'0\');\...
0
0
['Breadth-First Search', 'C']
0
valid-permutations-for-di-sequence
C++ Easy
c-easy-by-subhrajit123-18b8
class Solution {\npublic:\n int mod = 1e9 + 7;\n // unordered_setst;\n int perm(int i, int prev, int n, string &s, vector>&dp, vector&vis)\n {\n
Subhrajit123
NORMAL
2022-07-06T11:46:49.372375+00:00
2022-07-06T11:47:32.850386+00:00
262
false
class Solution {\npublic:\n int mod = 1e9 + 7;\n // unordered_set<int>st;\n int perm(int i, int prev, int n, string &s, vector<vector<int>>&dp, vector<bool>&vis)\n {\n //cout<<"HERE"<<i<<"\\n";\n if(i<0)\n {\n return 1;\n }\n if(dp[i][prev] != -1)\n {\n ...
0
0
['Dynamic Programming', 'C']
0
valid-permutations-for-di-sequence
EASY C++ SOLUTION DP | RECURSION | MEMOIZATION
easy-c-solution-dp-recursion-memoization-f8ar
\nclass Solution {\npublic:\n \n int dp[201][201];\n int m = 1e9+7;\n int helper(string &s, int i, vector<bool> &visit, int start){\n if(i==s
jatinbansal1179
NORMAL
2022-07-06T11:15:27.397477+00:00
2022-07-06T11:15:27.397526+00:00
548
false
```\nclass Solution {\npublic:\n \n int dp[201][201];\n int m = 1e9+7;\n int helper(string &s, int i, vector<bool> &visit, int start){\n if(i==s.length()){\n return 1;\n }\n \n if(dp[i][start]!=-1){\n return dp[i][start];\n }\n if(s[i]==\'D\'){...
0
0
['Dynamic Programming', 'Recursion', 'Memoization', 'C', 'C++']
1
valid-permutations-for-di-sequence
Easy C++ Solution
easy-c-solution-by-abhi-1301-iwp0
\nusing ll = long long;\n\nll dp[205][205];\nconst ll mod = 1e9 + 7;\nint n;\n\nll solve(int index, string &s, vector<int> &v, int piche)\n{\n if (index >= s
Abhi-1301
NORMAL
2022-07-06T10:10:12.451897+00:00
2022-07-06T10:10:12.451937+00:00
747
false
```\nusing ll = long long;\n\nll dp[205][205];\nconst ll mod = 1e9 + 7;\nint n;\n\nll solve(int index, string &s, vector<int> &v, int piche)\n{\n if (index >= s.size())\n return 1;\n\n if (dp[index][piche] != -1)\n return dp[index][piche];\n\n dp[index][piche] = 0;\n\n if (s[index] == \'D\')\n...
0
0
['Dynamic Programming', 'Memoization', 'C', 'C++']
2
valid-permutations-for-di-sequence
C# Solution
c-solution-by-rwdenier-iq42
\n//This is based on a couple others..\n//I take no credit other than the obvious refactoring.\n//I deliberately chose the one that seemed easier to understand,
rwdenier
NORMAL
2022-06-20T03:24:59.077889+00:00
2022-06-20T03:24:59.077929+00:00
93
false
```\n//This is based on a couple others..\n//I take no credit other than the obvious refactoring.\n//I deliberately chose the one that seemed easier to understand, not the fastest.\n\npublic class Solution \n{\n //Number of Permutations Table - Using long to avoid a lot of mod operations.\n long [,] np;\n int ...
0
0
[]
0
valid-permutations-for-di-sequence
🔥 First Javascript Solution
first-javascript-solution-by-joenix-91z1
\nfunction numPermsDISequence(s) {\n let mod = 1e9 + 7, dp = [[1], []], res = 0\n\n for (let i = 1; i <= S.length; i++) {\n for (let j = 0; j <= i;
joenix
NORMAL
2022-05-19T11:46:56.339096+00:00
2022-05-19T11:46:56.339136+00:00
88
false
```\nfunction numPermsDISequence(s) {\n let mod = 1e9 + 7, dp = [[1], []], res = 0\n\n for (let i = 1; i <= S.length; i++) {\n for (let j = 0; j <= i; j++) {\n let l = 0, r = j\n if (s.charAt(i-1) === \'D\') {\n l = j, r = i\n }\n dp[1][j] = 0\n ...
0
0
['JavaScript']
0
valid-permutations-for-di-sequence
C++ | Memoization solution
c-memoization-solution-by-diavolos-l3jb
```\nclass Solution {\nprivate:\n int n,mod=1000000000+7;\n vector>mem;\n int solve(string &s,int index,int prev,vector&seen){\n if(index==n){\n
Diavolos
NORMAL
2022-05-19T08:30:33.657073+00:00
2022-05-19T08:30:33.657114+00:00
692
false
```\nclass Solution {\nprivate:\n int n,mod=1000000000+7;\n vector<vector<int>>mem;\n int solve(string &s,int index,int prev,vector<bool>&seen){\n if(index==n){\n return 1;\n } else if(mem[index][prev]!=-1){\n return mem[index][prev];\n } else {\n int ans=0...
0
0
['Dynamic Programming', 'Memoization', 'C', 'C++']
1
valid-permutations-for-di-sequence
PYTHON SOLUTION || EASY || EXPLAINED || DP || WELL WRITTTEN CODE||
python-solution-easy-explained-dp-well-w-c30f
Try putting Value at the position keeping in mind that the current value should be increasing or decreasing \nTo check this check s[pos - 1] \nNow since we cann
reaper_27
NORMAL
2022-03-16T12:46:46.690586+00:00
2022-03-16T12:46:46.690613+00:00
456
false
Try putting Value at the position keeping in mind that the current value should be increasing or decreasing \nTo check this check s[pos - 1] \nNow since we cannot repeat any digit we should use a dictionary to keep in check what value we used so far .\n\nOnce you find the no. of answer having index = i and last item =...
0
0
['Dynamic Programming', 'Recursion', 'Memoization', 'Python', 'Python3']
1
valid-permutations-for-di-sequence
MEMOIZATION DP
memoization-dp-by-atharva20194080-jmgn
\nclass Solution {\npublic:\n int dp[203][203];\n int mod=1e9+7;\n int solve(int index , string& s, vector<int> & visited , int prev){\n if(inde
atharva20194080
NORMAL
2022-03-15T10:55:11.078320+00:00
2022-03-15T10:55:11.078347+00:00
177
false
```\nclass Solution {\npublic:\n int dp[203][203];\n int mod=1e9+7;\n int solve(int index , string& s, vector<int> & visited , int prev){\n if(index==s.size()) return 1;\n if(dp[index][prev]!=-1) return dp[index][prev];\n int n=s.size();\n long long temp=0;\n if(s[index]==\'D...
0
0
[]
1
valid-permutations-for-di-sequence
Compiling both O(n^2) approaches.
compiling-both-on2-approaches-by-josshei-92n4
The first approach is based on this post by lee215.\n\nIn both the cases we are avoiding looping through the values already looped through by the previous eleme
jossheim
NORMAL
2021-07-01T00:53:46.926865+00:00
2021-07-01T01:27:17.448990+00:00
422
false
The first approach is based on [this](https://leetcode.com/problems/valid-permutations-for-di-sequence/discuss/168278/C%2B%2BJavaPython-DP-Solution-O(N2)) post by lee215.\n\nIn both the cases we are avoiding looping through the values already looped through by the previous element by just using the previous values to m...
0
0
[]
0
valid-permutations-for-di-sequence
C++ Easy
c-easy-by-aaditya-pal-ouzv
c++\nclass Solution {\npublic:\n int n;\n string s;\n int mod = 1e9 + 7;\n map<pair<int,int>,int>dp;\n int countways(int id,int prev,vector<bool>
aaditya-pal
NORMAL
2021-05-29T20:35:28.717124+00:00
2021-05-29T20:35:28.717156+00:00
319
false
```c++\nclass Solution {\npublic:\n int n;\n string s;\n int mod = 1e9 + 7;\n map<pair<int,int>,int>dp;\n int countways(int id,int prev,vector<bool>&taken){\n\n if(id==n+1){\n return 1;\n }\n if(dp.find({id,prev})!=dp.end()) return dp[{id,prev}];\n int ans = 0;\n ...
0
0
[]
0
valid-permutations-for-di-sequence
Java - DP - O(N^3)
java-dp-on3-by-kataria_aakash-4kuh
\nclass Solution {\n int MOD = 1000000007;\n Map<Integer, Integer> cache;\n public int numPermsDISequence(String s) {\n cache = new HashMap<>();
kataria_aakash
NORMAL
2021-05-15T17:58:04.744129+00:00
2021-05-15T17:58:45.764806+00:00
237
false
```\nclass Solution {\n int MOD = 1000000007;\n Map<Integer, Integer> cache;\n public int numPermsDISequence(String s) {\n cache = new HashMap<>();\n return dpRec(s, 0, 0, s.length(), new boolean[s.length()+1]);\n }\n private int dpRec(String s, int i, int x, int y, boolean[] vis) {\n ...
0
0
[]
0