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apps_data_300
Given a single positive integer x, we will write an expression of the form x (op1) x (op2) x (op3) x ... where each operator op1, op2, etc. is either addition, subtraction, multiplication, or division (+, -, *, or /).  For example, with x = 3, we might write 3 * 3 / 3 + 3 - 3 which is a value of 3. When writing such an...
apps_data_301
We write the integers of A and B (in the order they are given) on two separate horizontal lines. Now, we may draw connecting lines: a straight line connecting two numbers A[i] and B[j] such that: A[i] == B[j]; The line we draw does not intersect any other connecting (non-horizontal) line. Note that a connecting lines...
apps_data_302
Given the coordinates of four points in 2D space, return whether the four points could construct a square. The coordinate (x,y) of a point is represented by an integer array with two integers. Example: Input: p1 = [0,0], p2 = [1,1], p3 = [1,0], p4 = [0,1] Output: True Note: All the input integers are in the ra...
apps_data_303
Given an integer array arr, you should partition the array into (contiguous) subarrays of length at most k. After partitioning, each subarray has their values changed to become the maximum value of that subarray. Return the largest sum of the given array after partitioning.   Example 1: Input: arr = [1,15,7,9,2,5,10], ...
apps_data_304
Some people will make friend requests. The list of their ages is given and ages[i] is the age of the ith person.  Person A will NOT friend request person B (B != A) if any of the following conditions are true: age[B] <= 0.5 * age[A] + 7 age[B] > age[A] age[B] > 100 && age[A] < 100 Otherwise, A will friend request B. ...
apps_data_305
Return the number of distinct non-empty substrings of text that can be written as the concatenation of some string with itself (i.e. it can be written as a + a where a is some string).   Example 1: Input: text = "abcabcabc" Output: 3 Explanation: The 3 substrings are "abcabc", "bcabca" and "cabcab". Example 2: Input: ...
apps_data_306
Given an integer array with all positive numbers and no duplicates, find the number of possible combinations that add up to a positive integer target. Example: nums = [1, 2, 3] target = 4 The possible combination ways are: (1, 1, 1, 1) (1, 1, 2) (1, 2, 1) (1, 3) (2, 1, 1) (2, 2) (3, 1) Note that different sequences...
apps_data_307
There are two types of soup: type A and type B. Initially we have N ml of each type of soup. There are four kinds of operations: Serve 100 ml of soup A and 0 ml of soup B Serve 75 ml of soup A and 25 ml of soup B Serve 50 ml of soup A and 50 ml of soup B Serve 25 ml of soup A and 75 ml of soup B When we serve some so...
apps_data_308
Given a string representing a code snippet, you need to implement a tag validator to parse the code and return whether it is valid. A code snippet is valid if all the following rules hold: The code must be wrapped in a valid closed tag. Otherwise, the code is invalid. A closed tag (not necessarily valid) has exactly t...
apps_data_309
Given an array A of integers, return the length of the longest arithmetic subsequence in A. Recall that a subsequence of A is a list A[i_1], A[i_2], ..., A[i_k] with 0 <= i_1 < i_2 < ... < i_k <= A.length - 1, and that a sequence B is arithmetic if B[i+1] - B[i] are all the same value (for 0 <= i < B.length - 1).   Exa...
apps_data_310
Given a non-negative integer N, find the largest number that is less than or equal to N with monotone increasing digits. (Recall that an integer has monotone increasing digits if and only if each pair of adjacent digits x and y satisfy x .) Example 1: Input: N = 10 Output: 9 Example 2: Input: N = 1234 Output: 1...
apps_data_311
There are N children standing in a line. Each child is assigned a rating value. You are giving candies to these children subjected to the following requirements: Each child must have at least one candy. Children with a higher rating get more candies than their neighbors. What is the minimum candies y...
apps_data_312
Return the length of the shortest, non-empty, contiguous subarray of A with sum at least K. If there is no non-empty subarray with sum at least K, return -1.   Example 1: Input: A = [1], K = 1 Output: 1 Example 2: Input: A = [1,2], K = 4 Output: -1 Example 3: Input: A = [2,-1,2], K = 3 Output: 3   Note: 1 <= A...
apps_data_313
Given an integer array bloomDay, an integer m and an integer k. We need to make m bouquets. To make a bouquet, you need to use k adjacent flowers from the garden. The garden consists of n flowers, the ith flower will bloom in the bloomDay[i] and then can be used in exactly one bouquet. Return the minimum number of days...
apps_data_314
Given a binary string s (a string consisting only of '0' and '1's). Return the number of substrings with all characters 1's. Since the answer may be too large, return it modulo 10^9 + 7.   Example 1: Input: s = "0110111" Output: 9 Explanation: There are 9 substring in total with only 1's characters. "1" -> 5 times. "11...
apps_data_315
You are given two strings s1 and s2 of equal length consisting of letters "x" and "y" only. Your task is to make these two strings equal to each other. You can swap any two characters that belong to different strings, which means: swap s1[i] and s2[j]. Return the minimum number of swaps required to make s1 and s2 equal...
apps_data_316
A string is called a happy prefix if is a non-empty prefix which is also a suffix (excluding itself). Given a string s. Return the longest happy prefix of s . Return an empty string if no such prefix exists.   Example 1: Input: s = "level" Output: "l" Explanation: s contains 4 prefix excluding itself ("l", "le", "lev",...
apps_data_317
We are given S, a length n string of characters from the set {'D', 'I'}. (These letters stand for "decreasing" and "increasing".) A valid permutation is a permutation P[0], P[1], ..., P[n] of integers {0, 1, ..., n}, such that for all i: If S[i] == 'D', then P[i] > P[i+1], and; If S[i] == 'I', then P[i] < P[i+1]. How...
apps_data_318
There is a pizza with 3n slices of varying size, you and your friends will take slices of pizza as follows: You will pick any pizza slice. Your friend Alice will pick next slice in anti clockwise direction of your pick.  Your friend Bob will pick next slice in clockwise direction of your pick. Repeat until there are n...
apps_data_319
Alice and Bob continue their games with piles of stones. There are several stones arranged in a row, and each stone has an associated value which is an integer given in the array stoneValue. Alice and Bob take turns, with Alice starting first. On each player's turn, that player can take 1, 2 or 3 stones from the first ...
apps_data_320
Your task is to form an integer array nums from an initial array of zeros arr that is the same size as nums. Return the minimum number of function calls to make nums from arr. The answer is guaranteed to fit in a 32-bit signed integer.   Example 1: Input: nums = [1,5] Output: 5 Explanation: Increment by 1 (second eleme...
apps_data_321
Given two strings: s1 and s2 with the same size, check if some permutation of string s1 can break some permutation of string s2 or vice-versa (in other words s2 can break s1). A string x can break string y (both of size n) if x[i] >= y[i] (in alphabetical order) for all i between 0 and n-1.   Example 1: Input: s1 = "ab...
apps_data_322
Given a sorted positive integer array nums and an integer n, add/patch elements to the array such that any number in range [1, n] inclusive can be formed by the sum of some elements in the array. Return the minimum number of patches required. Example 1: Input: nums = [1,3], n = 6 Output: 1 Explanation: Combinations...
apps_data_323
Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2. Example 1: Input: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac" Output: true Example 2: Input: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbbaccc" Output: false class Solution: def isInterleave(self, s1, s2, s3): """ ...
apps_data_324
Given a positive 32-bit integer n, you need to find the smallest 32-bit integer which has exactly the same digits existing in the integer n and is greater in value than n. If no such positive 32-bit integer exists, you need to return -1. Example 1: Input: 12 Output: 21   Example 2: Input: 21 Output: -1 class S...
apps_data_325
Given an N x N grid containing only values 0 and 1, where 0 represents water and 1 represents land, find a water cell such that its distance to the nearest land cell is maximized and return the distance. The distance used in this problem is the Manhattan distance: the distance between two cells (x0, y0) and (x1, y1) is...
apps_data_326
The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAPLSIIGYIR" Write the code that will take a string and make this conver...
apps_data_327
Given a string, find the length of the longest substring without repeating characters. Examples: Given "abcabcbb", the answer is "abc", which the length is 3. Given "bbbbb", the answer is "b", with the length of 1. Given "pwwkew", the answer is "wke", with the length of 3. Note that the answer must be a substring, ...
apps_data_328
Given a sequence of n integers a1, a2, ..., an, a 132 pattern is a subsequence ai, aj, ak such that i < j < k and ai < ak < aj. Design an algorithm that takes a list of n numbers as input and checks whether there is a 132 pattern in the list. Note: n will be less than 15,000. Example 1: Input: [1, 2, 3, 4] Output: ...
apps_data_329
You are given a rows x cols matrix grid. Initially, you are located at the top-left corner (0, 0), and in each step, you can only move right or down in the matrix. Among all possible paths starting from the top-left corner (0, 0) and ending in the bottom-right corner (rows - 1, cols - 1), find the path with the maximum...
apps_data_330
Validate if a given string is numeric. Some examples: "0" => true " 0.1 " => true "abc" => false "1 a" => false "2e10" => true Note: It is intended for the problem statement to be ambiguous. You should gather all requirements up front before implementing one. Update (2015-02-10): The signature of the C++ function ha...
apps_data_331
Given two numbers, hour and minutes. Return the smaller angle (in degrees) formed between the hour and the minute hand.   Example 1: Input: hour = 12, minutes = 30 Output: 165 Example 2: Input: hour = 3, minutes = 30 Output: 75 Example 3: Input: hour = 3, minutes = 15 Output: 7.5 Example 4: Input: hour = 4, minut...
apps_data_332
Given a string, your task is to count how many palindromic substrings in this string. The substrings with different start indexes or end indexes are counted as different substrings even they consist of same characters. Example 1: Input: "abc" Output: 3 Explanation: Three palindromic strings: "a", "b", "c". Ex...
apps_data_333
Given an array of integers arr, you are initially positioned at the first index of the array. In one step you can jump from index i to index: i + 1 where: i + 1 < arr.length. i - 1 where: i - 1 >= 0. j where: arr[i] == arr[j] and i != j. Return the minimum number of steps to reach the last index of the array. Notice ...
apps_data_334
Given a string s and an array of integers cost where cost[i] is the cost of deleting the ith character in s. Return the minimum cost of deletions such that there are no two identical letters next to each other. Notice that you will delete the chosen characters at the same time, in other words, after deleting a characte...
apps_data_335
You are installing a billboard and want it to have the largest height.  The billboard will have two steel supports, one on each side.  Each steel support must be an equal height. You have a collection of rods which can be welded together.  For example, if you have rods of lengths 1, 2, and 3, you can weld them together...
apps_data_336
Given two equal-size strings s and t. In one step you can choose any character of t and replace it with another character. Return the minimum number of steps to make t an anagram of s. An Anagram of a string is a string that contains the same characters with a different (or the same) ordering.   Example 1: Input: s = "...
apps_data_337
There are N gas stations along a circular route, where the amount of gas at station i is gas[i]. You have a car with an unlimited gas tank and it costs cost[i] of gas to travel from station i to its next station (i+1). You begin the journey with an empty tank at one of the gas stations. Return the starting gas statio...
apps_data_338
Given the strings s1 and s2 of size n, and the string evil. Return the number of good strings. A good string has size n, it is alphabetically greater than or equal to s1, it is alphabetically smaller than or equal to s2, and it does not contain the string evil as a substring. Since the answer can be a huge number, retu...
apps_data_339
Given two arrays of integers nums1 and nums2, return the number of triplets formed (type 1 and type 2) under the following rules: Type 1: Triplet (i, j, k) if nums1[i]2 == nums2[j] * nums2[k] where 0 <= i < nums1.length and 0 <= j < k < nums2.length. Type 2: Triplet (i, j, k) if nums2[i]2 == nums1[j] * nums1[k] where ...
apps_data_340
Given an absolute path for a file (Unix-style), simplify it. For example, path = "/home/", => "/home" path = "/a/./b/../../c/", => "/c" Corner Cases: Did you consider the case where path = "/../"? In this case, you should return "/". Another corner case is the path might contain multiple slashe...
apps_data_341
Write a program to find the n-th ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5.  Example: Input: n = 10 Output: 12 Explanation: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12 is the sequence of the first 10 ugly numbers. Note:   1 is typically treated as an ugly number. n ...
apps_data_342
Given an 2D board, count how many battleships are in it. The battleships are represented with 'X's, empty slots are represented with '.'s. You may assume the following rules: You receive a valid board, made of only battleships or empty slots. Battleships can only be placed horizontally or vertically. In other words, ...
apps_data_343
Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, ...) which sum to n. Example 1: Input: n = 12 Output: 3 Explanation: 12 = 4 + 4 + 4. Example 2: Input: n = 13 Output: 2 Explanation: 13 = 4 + 9. class Solution: def numSquares(self, n): """ ...
apps_data_344
We are given an array A of N lowercase letter strings, all of the same length. Now, we may choose any set of deletion indices, and for each string, we delete all the characters in those indices. For example, if we have an array A = ["babca","bbazb"] and deletion indices {0, 1, 4}, then the final array after deletions i...
apps_data_345
Given an array which consists of non-negative integers and an integer m, you can split the array into m non-empty continuous subarrays. Write an algorithm to minimize the largest sum among these m subarrays. Note: If n is the length of array, assume the following constraints are satisfied: 1 ≤ n ≤ 1000 1 ≤ m ≤ min(5...
apps_data_346
Given an array of integers nums and an integer k. A continuous subarray is called nice if there are k odd numbers on it. Return the number of nice sub-arrays.   Example 1: Input: nums = [1,1,2,1,1], k = 3 Output: 2 Explanation: The only sub-arrays with 3 odd numbers are [1,1,2,1] and [1,2,1,1]. Example 2: Input: nums ...
apps_data_347
Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutations is the substring of the second string. Example 1: Input:s1 = "ab" s2 = "eidbaooo" Output:True Explanation: s2 contains one permutation of s1 ("ba"). Example 2: ...
apps_data_348
Given an array of integers, return the maximum sum for a non-empty subarray (contiguous elements) with at most one element deletion. In other words, you want to choose a subarray and optionally delete one element from it so that there is still at least one element left and the sum of the remaining elements is maximum p...
apps_data_349
Given an array nums of integers, you can perform operations on the array. In each operation, you pick any nums[i] and delete it to earn nums[i] points. After, you must delete every element equal to nums[i] - 1 or nums[i] + 1. You start with 0 points. Return the maximum number of points you can earn by applying such...
apps_data_350
Given an array A of positive integers, call a (contiguous, not necessarily distinct) subarray of A good if the number of different integers in that subarray is exactly K. (For example, [1,2,3,1,2] has 3 different integers: 1, 2, and 3.) Return the number of good subarrays of A.   Example 1: Input: A = [1,2,1,2,3], K = ...
apps_data_351
On a broken calculator that has a number showing on its display, we can perform two operations: Double: Multiply the number on the display by 2, or; Decrement: Subtract 1 from the number on the display. Initially, the calculator is displaying the number X. Return the minimum number of operations needed to display the...
apps_data_352
Given a list of words, each word consists of English lowercase letters. Let's say word1 is a predecessor of word2 if and only if we can add exactly one letter anywhere in word1 to make it equal to word2.  For example, "abc" is a predecessor of "abac". A word chain is a sequence of words [word_1, word_2, ..., word_k] wi...
apps_data_353
Given an array of integers nums and an integer target. Return the number of non-empty subsequences of nums such that the sum of the minimum and maximum element on it is less or equal than target. Since the answer may be too large, return it modulo 10^9 + 7.   Example 1: Input: nums = [3,5,6,7], target = 9 Output: 4 Exp...
apps_data_354
A die simulator generates a random number from 1 to 6 for each roll. You introduced a constraint to the generator such that it cannot roll the number i more than rollMax[i] (1-indexed) consecutive times.  Given an array of integers rollMax and an integer n, return the number of distinct sequences that can be obtained w...
apps_data_355
Given integers n and k, find the lexicographically k-th smallest integer in the range from 1 to n. Note: 1 ≤ k ≤ n ≤ 109. Example: Input: n: 13 k: 2 Output: 10 Explanation: The lexicographical order is [1, 10, 11, 12, 13, 2, 3, 4, 5, 6, 7, 8, 9], so the second smallest number is 10. class Solution(object): ...
apps_data_356
Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first integer of each row is greater than the last integer of the previous row. Example 1: Input: matrix = [ [1, 3, 5, 7]...
apps_data_357
You are given an array representing a row of seats where seats[i] = 1 represents a person sitting in the ith seat, and seats[i] = 0 represents that the ith seat is empty (0-indexed). There is at least one empty seat, and at least one person sitting. Alex wants to sit in the seat such that the distance between him and t...
apps_data_358
To some string S, we will perform some replacement operations that replace groups of letters with new ones (not necessarily the same size). Each replacement operation has 3 parameters: a starting index i, a source word x and a target word y.  The rule is that if x starts at position i in the original string S, then we ...
apps_data_359
Given a square array of integers A, we want the minimum sum of a falling path through A. A falling path starts at any element in the first row, and chooses one element from each row.  The next row's choice must be in a column that is different from the previous row's column by at most one.   Example 1: Input: [[1,2,3],...
apps_data_360
A conveyor belt has packages that must be shipped from one port to another within D days. The i-th package on the conveyor belt has a weight of weights[i].  Each day, we load the ship with packages on the conveyor belt (in the order given by weights). We may not load more weight than the maximum weight capacity of the ...
apps_data_361
Given a rectangle of size n x m, find the minimum number of integer-sided squares that tile the rectangle.   Example 1: Input: n = 2, m = 3 Output: 3 Explanation: 3 squares are necessary to cover the rectangle. 2 (squares of 1x1) 1 (square of 2x2) Example 2: Input: n = 5, m = 8 Output: 5 Example 3: Input: n = 11, m...
apps_data_362
There are n people and 40 types of hats labeled from 1 to 40. Given a list of list of integers hats, where hats[i] is a list of all hats preferred by the i-th person. Return the number of ways that the n people wear different hats to each other. Since the answer may be too large, return it modulo 10^9 + 7.   Example 1:...
apps_data_363
Given a 2D array A, each cell is 0 (representing sea) or 1 (representing land) A move consists of walking from one land square 4-directionally to another land square, or off the boundary of the grid. Return the number of land squares in the grid for which we cannot walk off the boundary of the grid in any number of mov...
apps_data_364
You are given two jugs with capacities x and y litres. There is an infinite amount of water supply available. You need to determine whether it is possible to measure exactly z litres using these two jugs. If z liters of water is measurable, you must have z liters of water contained within one or both buckets by the en...
apps_data_365
Let's define a function countUniqueChars(s) that returns the number of unique characters on s, for example if s = "LEETCODE" then "L", "T","C","O","D" are the unique characters since they appear only once in s, therefore countUniqueChars(s) = 5. On this problem given a string s we need to return the sum of countUnique...
apps_data_366
Find the length of the longest substring T of a given string (consists of lowercase letters only) such that every character in T appears no less than k times. Example 1: Input: s = "aaabb", k = 3 Output: 3 The longest substring is "aaa", as 'a' is repeated 3 times. Example 2: Input: s = "ababbc", k = 2 Output...
apps_data_367
Given an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), prove that at least one duplicate number must exist. Assume that there is only one duplicate number, find the duplicate one. Example 1: Input: [1,3,4,2,2] Output: 2 Example 2: Input: [3,1,3,4,2] Output: 3 Note: ...
apps_data_368
A chef has collected data on the satisfaction level of his n dishes. Chef can cook any dish in 1 unit of time. Like-time coefficient of a dish is defined as the time taken to cook that dish including previous dishes multiplied by its satisfaction level  i.e.  time[i]*satisfaction[i] Return the maximum sum of Like-time ...
apps_data_369
Given a m x n binary matrix mat. In one step, you can choose one cell and flip it and all the four neighbours of it if they exist (Flip is changing 1 to 0 and 0 to 1). A pair of cells are called neighboors if they share one edge. Return the minimum number of steps required to convert mat to a zero matrix or -1 if you c...
apps_data_370
Given a non-empty array of unique positive integers A, consider the following graph: There are A.length nodes, labelled A[0] to A[A.length - 1]; There is an edge between A[i] and A[j] if and only if A[i] and A[j] share a common factor greater than 1. Return the size of the largest connected component in the graph.   ...
apps_data_371
We have a list of bus routes. Each routes[i] is a bus route that the i-th bus repeats forever. For example if routes[0] = [1, 5, 7], this means that the first bus (0-th indexed) travels in the sequence 1->5->7->1->5->7->1->... forever. We start at bus stop S (initially not on a bus), and we want to go to bus stop T. Tr...
apps_data_372
Given an input string (s) and a pattern (p), implement regular expression matching with support for '.' and '*'. '.' Matches any single character. '*' Matches zero or more of the preceding element. The matching should cover the entire input string (not partial). Note: s could be empty and contains only lo...
apps_data_373
Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most k transactions. Note: You may not engage in multiple transactions at the same time (ie, you must sell the stock before you buy again). Example 1: Input: [...
apps_data_374
Given an array A of strings, find any smallest string that contains each string in A as a substring. We may assume that no string in A is substring of another string in A.   Example 1: Input: ["alex","loves","leetcode"] Output: "alexlovesleetcode" Explanation: All permutations of "alex","loves","leetcode" would also b...
apps_data_375
Given an unsorted array, find the maximum difference between the successive elements in its sorted form. Return 0 if the array contains less than 2 elements. Example 1: Input: [3,6,9,1] Output: 3 Explanation: The sorted form of the array is [1,3,6,9], either   (3,6) or (6,9) has the maximum difference 3....
apps_data_376
Given N, consider a convex N-sided polygon with vertices labelled A[0], A[i], ..., A[N-1] in clockwise order. Suppose you triangulate the polygon into N-2 triangles.  For each triangle, the value of that triangle is the product of the labels of the vertices, and the total score of the triangulation is the sum of these ...
apps_data_377
A positive integer is magical if it is divisible by either A or B. Return the N-th magical number.  Since the answer may be very large, return it modulo 10^9 + 7.   Example 1: Input: N = 1, A = 2, B = 3 Output: 2 Example 2: Input: N = 4, A = 2, B = 3 Output: 6 Example 3: Input: N = 5, A = 2, B = 4 Output: 10 E...
apps_data_378
Given a non-empty array containing only positive integers, find if the array can be partitioned into two subsets such that the sum of elements in both subsets is equal. Note: Each of the array element will not exceed 100. The array size will not exceed 200. Example 1: Input: [1, 5, 11, 5] Output: true Explanat...
apps_data_379
You are given two sorted arrays of distinct integers nums1 and nums2. A valid path is defined as follows: Choose array nums1 or nums2 to traverse (from index-0). Traverse the current array from left to right. If you are reading any value that is present in nums1 and nums2 you are allowed to change your path to the oth...
apps_data_380
Write a function to check whether an input string is a valid IPv4 address or IPv6 address or neither. IPv4 addresses are canonically represented in dot-decimal notation, which consists of four decimal numbers, each ranging from 0 to 255, separated by dots ("."), e.g.,172.16.254.1; Besides, leading zeros in the IP...
apps_data_381
Given an array of n positive integers and a positive integer s, find the minimal length of a contiguous subarray of which the sum ≥ s. If there isn't one, return 0 instead. Example:  Input: s = 7, nums = [2,3,1,2,4,3] Output: 2 Explanation: the subarray [4,3] has the minimal length under the problem constraint. Fol...
apps_data_382
A peak element is an element that is greater than its neighbors. Given an input array nums, where nums[i] ≠ nums[i+1], find a peak element and return its index. The array may contain multiple peaks, in that case return the index to any one of the peaks is fine. You may imagine that nums[-1] = nums[n] = -∞. Example ...
apps_data_383
(This problem is the same as Minimize Malware Spread, with the differences bolded.) In a network of nodes, each node i is directly connected to another node j if and only if graph[i][j] = 1. Some nodes initial are initially infected by malware.  Whenever two nodes are directly connected and at least one of those two no...
apps_data_384
Given an array of integers A, consider all non-empty subsequences of A. For any sequence S, let the width of S be the difference between the maximum and minimum element of S. Return the sum of the widths of all subsequences of A.  As the answer may be very large, return the answer modulo 10^9 + 7.   Example 1: Input: ...
apps_data_385
Given two positive integers n and k. A factor of an integer n is defined as an integer i where n % i == 0. Consider a list of all factors of n sorted in ascending order, return the kth factor in this list or return -1 if n has less than k factors.   Example 1: Input: n = 12, k = 3 Output: 3 Explanation: Factors list is...
apps_data_386
Given an integer n, your task is to count how many strings of length n can be formed under the following rules: Each character is a lower case vowel ('a', 'e', 'i', 'o', 'u') Each vowel 'a' may only be followed by an 'e'. Each vowel 'e' may only be followed by an 'a' or an 'i'. Each vowel 'i' may not be followed by an...
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In a special ranking system, each voter gives a rank from highest to lowest to all teams participated in the competition. The ordering of teams is decided by who received the most position-one votes. If two or more teams tie in the first position, we consider the second position to resolve the conflict, if they tie aga...
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Given an array of citations (each citation is a non-negative integer) of a researcher, write a function to compute the researcher's h-index. According to the definition of h-index on Wikipedia: "A scientist has index h if h of his/her N papers have at least h citations each, and the other N − h papers have no more tha...
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In a given integer array A, we must move every element of A to either list B or list C. (B and C initially start empty.) Return true if and only if after such a move, it is possible that the average value of B is equal to the average value of C, and B and C are both non-empty. Example : Input: [1,2,3,4,5,6,7,8] Output...
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Alice and Bob take turns playing a game, with Alice starting first. Initially, there are n stones in a pile.  On each player's turn, that player makes a move consisting of removing any non-zero square number of stones in the pile. Also, if a player cannot make a move, he/she loses the game. Given a positive integer n. ...
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Define S = [s,n] as the string S which consists of n connected strings s. For example, ["abc", 3] ="abcabcabc". On the other hand, we define that string s1 can be obtained from string s2 if we can remove some characters from s2 such that it becomes s1. For example, “abc” can be obtained from “abdbec” based on our def...
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Given a binary string s (a string consisting only of '0's and '1's), we can split s into 3 non-empty strings s1, s2, s3 (s1+ s2+ s3 = s). Return the number of ways s can be split such that the number of characters '1' is the same in s1, s2, and s3. Since the answer may be too large, return it modulo 10^9 + 7.   Example...
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Write a program to find the n-th ugly number. Ugly numbers are positive integers which are divisible by a or b or c.   Example 1: Input: n = 3, a = 2, b = 3, c = 5 Output: 4 Explanation: The ugly numbers are 2, 3, 4, 5, 6, 8, 9, 10... The 3rd is 4. Example 2: Input: n = 4, a = 2, b = 3, c = 4 Output: 6 Explanation: The...
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Given a non-empty integer array, find the minimum number of moves required to make all array elements equal, where a move is incrementing a selected element by 1 or decrementing a selected element by 1. You may assume the array's length is at most 10,000. Example: Input: [1,2,3] Output: 2 Explanation: Only two mov...
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You are given an integer array A.  From some starting index, you can make a series of jumps.  The (1st, 3rd, 5th, ...) jumps in the series are called odd numbered jumps, and the (2nd, 4th, 6th, ...) jumps in the series are called even numbered jumps. You may from index i jump forward to index j (with i < j) in the foll...
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Given a positive integer K, you need find the smallest positive integer N such that N is divisible by K, and N only contains the digit 1. Return the length of N.  If there is no such N, return -1.   Example 1: Input: 1 Output: 1 Explanation: The smallest answer is N = 1, which has length 1. Example 2: Input: 2 Output: ...
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Given an integer n, count the total number of digit 1 appearing in all non-negative integers less than or equal to n. Example: Input: 13 Output: 6 Explanation: Digit 1 occurred in the following numbers: 1, 10, 11, 12, 13. class Solution: def countDigitOne(self, n): """ :type n: int ...
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Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers in the array is [-1000, 1000] and the range of the integer k is...
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A message containing letters from A-Z is being encoded to numbers using the following mapping: 'A' -> 1 'B' -> 2 ... 'Z' -> 26 Given a non-empty string containing only digits, determine the total number of ways to decode it. Example 1: Input: "12" Output: 2 Explanation: It could be decoded as "AB" (1 2) or "L" (...