摘要：
There are n students in a class numbered from 0 to n - 1. The teacher will give each student a problem starting with the student number 0, then the st 阅读全文
摘要：
Given an array points where points[i] = [xi, yi] represents a point on the X-Y plane, return true if these points are a boomerang. A boomerang is a se 阅读全文
摘要：
Given the root of a binary tree, return the number of nodes where the value of the node is equal to the sum of the values of its descendants. A descen 阅读全文
摘要：
A newly designed keypad was tested, where a tester pressed a sequence of n keys, one at a time. You are given a string keysPressed of length n, where 阅读全文
摘要：
You are given a string s, and an array of pairs of indices in the string pairs where pairs[i] = [a, b] indicates 2 indices(0-indexed) of the string. Y 阅读全文
摘要：
Given the API rand7() that generates a uniform random integer in the range [1, 7], write a function rand10() that generates a uniform random integer i 阅读全文
摘要：
You are given a 0-indexed integer array nums, where nums[i] represents the score of the ith student. You are also given an integer k. Pick the scores 阅读全文
摘要：
Given an array of positive integers arr, calculate the sum of all possible odd-length subarrays. A subarray is a contiguous subsequence of the array. 阅读全文
摘要：
Given the root of a Binary Search Tree and a target number k, return true if there exist two elements in the BST such that their sum is equal to the g 阅读全文
摘要：
Given an array of strings nums containing n unique binary strings each of length n, return a binary string of length n that does not appear in nums. I 阅读全文
摘要：
Given the root of a binary tree, split the binary tree into two subtrees by removing one edge such that the product of the sums of the subtrees is max 阅读全文
摘要：
Given an array nums, you are allowed to choose one element of nums and change it by any value in one move. Return the minimum difference between the l 阅读全文
摘要：
Given an integer n, count the total number of digit 1 appearing in all non-negative integers less than or equal to n. Example 1: Input: n = 13 Output: 阅读全文
摘要：
You are given a 0-indexed string s of even length n. The string consists of exactly n / 2 opening brackets '[' and n / 2 closing brackets ']'. A strin 阅读全文
摘要：
Given an array of positive integers arr (not necessarily distinct), return the lexicographically largest permutation that is smaller than arr, that ca 阅读全文
摘要：
You are given a 0-indexed integer array piles, where piles[i] represents the number of stones in the ith pile, and an integer k. You should apply the 阅读全文
摘要：
Given a string s and an array of strings words, determine whether s is a prefix string of words. A string s is a prefix string of words if s can be ma 阅读全文
摘要：
A super ugly number is a positive integer whose prime factors are in the array primes. Given an integer n and an array of integers primes, return the 阅读全文
摘要：
You are playing a game involving a circular array of non-zero integers nums. Each nums[i] denotes the number of indices forward/backward you must move 阅读全文
摘要：
The Tribonacci sequence Tn is defined as follows: T0 = 0, T1 = 1, T2 = 1, and Tn+3 = Tn + Tn+1 + Tn+2 for n >= 0. Given n, return the value of Tn. Exa 阅读全文