Write an algorithm to determine if a number is “happy”. A happy number is a number defined …

  Given an array of n positive integers and a positive integer s, find the minimal length …

  You are playing a simplified Pacman game. You start at the point (0, 0), and your destination…

题目描述 Invert a binary tree. 4 / \ 2 7 / \ / \ 1 3 6 9 to 4 / \ 7 2 / \ / \ 9 6 3 1 Trivia: This problem was ins…

  Given a string s consists of upper/lower-case alphabets and empty space characters ' ', …

  A character in UTF8 can be from 1 to 4 bytes long, subjected to the following rules: For 1-byte charact…

题目地址：https://leetcode-cn.com/probl…题目描述：给定一个保存员工信息的数据结构，它包含了员工唯一的id，重要度 和 直系下属的id。 比如，员工1是员工2的领导，员工2是员工3…

44. Wildcard Matching 题目 Implement regular expression matching with support for '.' and '*'. '.' Matches any s…

欢迎fork and star：Nowcoder-Repository-github 152. Maximum Product Subarray 题目 Find the contiguous subarray withi…

  A self-dividing number is a number that is divisible by every digit it contains. For example,…

  A peak element is an element that is greater than its neighbors. Given an input array nums, where&…

  Given an array of size n, find the majority element. The majority element is the element that appe…