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题目 Given an m x n binary matrix mat, return the distance of the nearest 0 for each cell. The distance between two adjacent cells is 1. Ex…

Given two strings s1 and s2, return true if s2 contains a permutation of s1, or false otherwise. In other words, return true if one of s1's…

Given the head of a singly linked list, reverse the list, and return the reversed list. Given the head of a singly linked list, reverse…

You are given the heads of two sorted linked lists list1 and list2. Merge the two lists in a one sorted list. The list should be made by…

You are given two binary trees root1 and root2. Imagine that when you put one of them to cover the other, some nodes of the two trees are…

You are given a perfect binary tree where all leaves are on the same level, and every parent has two children. The binary tree has the…

You are given an m x n binary matrix grid. An island is a group of 1's (representing land) connected 4-directionally (horizontal or…

876. Middle of the Linked List Given the head of a singly linked list, return the middle node of the linked list. If there are two middle…

Two Sum II - Input Array Is Sorted Given a 1-indexed array of integers numbers that is already sorted in non-decreasing order, find two…

Reverse Words in a String III Given a string s, reverse the order of characters in each word within a sentence while still preserving…

Given an integer array nums, move all 0's to the end of it while maintaining the relative order of the non-zero elements. Note that you…

Given an array, rotate the array to the right by k steps, where k is non-negative. Example 1: Copy Input: nums = [1,2,3,4,5,6,7], k = 3…

Given an integer array nums sorted in non-decreasing order, return an array of the squares of each number sorted in non-decreasing order.…

BinarySearch Given an array of integers nums which is sorted in ascending order, and an integer target, write a function to search target…