原文链接: https://leetcode-cn.com/problems/longest-palindrome 英文原文Given a string s which consists of lowercase or uppercase letters, return the length of the longest palindrome that can be built with those letters. Letters are case sensitive, for example…

原文链接: https://leetcode-cn.com/problems/split-array-largest-sum 英文原文Given an array nums 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…

原文链接: https://leetcode-cn.com/problems/elimination-game 英文原文You have a list arr of all integers in the range [1, n] sorted in a strictly increasing order. Apply the following algorithm on arr: Starting from left to right, remove the first number and …

原文链接: https://leetcode-cn.com/problems/binary-watch 英文原文A binary watch has 4 LEDs on the top which represent the hours (0-11), and the 6 LEDs on the bottom represent the minutes (0-59). Each LED represents a zero or one, with the least significant bi…

原文链接: https://leetcode-cn.com/problems/fizz-buzz 英文原文Given an integer n, return a string array answer (1-indexed) where: answer[i] == "FizzBuzz" if i is divisible by 3 and 5. answer[i] == "Fizz" if i is divisible by 3. answer[i] == "Buzz" if i is div…

原文链接: https://leetcode-cn.com/problems/third-maximum-number 英文原文Given an integer array nums, return the third distinct maximum number in this array. If the third maximum does not exist, return the maximum number. Example 1: Input: nums = [3,2,1] Outp…

原文链接: https://leetcode-cn.com/problems/add-strings 英文原文Given two non-negative integers, num1 and num2 represented as string, return the sum of num1 and num2 as a string. You must solve the problem without using any built-in library for handling large…

原文链接: https://leetcode-cn.com/problems/partition-equal-subset-sum 英文原文Given a non-empty array nums 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. Exampl…

原文链接: https://leetcode-cn.com/problems/pacific-atlantic-water-flow 英文原文There is an m x n rectangular island that borders both the Pacific Ocean and Atlantic Ocean. The Pacific Ocean touches the island's left and top edges, and the Atlantic Ocean touc…

原文链接: https://leetcode-cn.com/problems/battleships-in-a-board 英文原文Given an m x n matrix board where each cell is a battleship 'X' or empty '.', return the number of the battleships on board. Battleships can only be placed horizontally or vertically o…

原文链接: https://leetcode-cn.com/problems/strong-password-checker 英文原文A password is considered strong if the below conditions are all met: It has at least 6 characters and at most 20 characters. It contains at least one lowercase letter, at least one up…

原文链接: https://leetcode-cn.com/problems/maximum-xor-of-two-numbers-in-an-array 英文原文Given an integer array nums, return the maximum result of nums[i] XOR nums[j], where 0 <= i <= j < n. Example 1: Input: nums = [3,10,5,25,2,8] Output: 28 Explanation: T…

原文链接: https://leetcode-cn.com/problems/reconstruct-original-digits-from-english 英文原文Given a string s containing an out-of-order English representation of digits 0-9, return the digits in ascending order. Example 1: Input: s = "owoztneoer" Output: "01…

原文链接: https://leetcode-cn.com/problems/all-oone-data-structure 英文原文Design a data structure to store the strings' count with the ability to return the strings with minimum and maximum counts. Implement the AllOne class: AllOne() Initializes the object…

原文链接: https://leetcode-cn.com/problems/minimum-genetic-mutation 英文原文A gene string can be represented by an 8-character long string, with choices from 'A', 'C', 'G', and 'T'. Suppose we need to investigate a mutation from a gene string start to a gene…

原文链接: https://leetcode-cn.com/problems/number-of-segments-in-a-string 英文原文You are given a string s, return the number of segments in the string. A segment is defined to be a contiguous sequence of non-space characters. Example 1: Input: s = "Hello, m…

原文链接: https://leetcode-cn.com/problems/non-overlapping-intervals 英文原文Given an array of intervals intervals where intervals[i] = [starti, endi], return the minimum number of intervals you need to remove to make the rest of the intervals non-overlappin…

原文链接: https://leetcode-cn.com/problems/find-right-interval 英文原文You are given an array of intervals, where intervals[i] = [starti, endi] and each starti is unique. The right interval for an interval i is an interval j such that startj >= endi and star…

原文链接: https://leetcode-cn.com/problems/path-sum-iii 英文原文Given the root of a binary tree and an integer targetSum, return the number of paths where the sum of the values along the path equals targetSum. The path does not need to start or end at the ro…

原文链接: https://leetcode-cn.com/problems/find-all-anagrams-in-a-string 英文原文Given two strings s and p, return an array of all the start indices of p's anagrams in s. You may return the answer in any order. An Anagram is a word or phrase formed by rearra…

原文链接: https://leetcode-cn.com/problems/k-th-smallest-in-lexicographical-order 英文原文Given two integers n and k, return the kth lexicographically smallest integer in the range [1, n]. Example 1: Input: n = 13, k = 2 Output: 10 Explanation: The lexicogra…

原文链接: https://leetcode-cn.com/problems/find-all-duplicates-in-an-array 英文原文Given an integer array nums of length n where all the integers of nums are in the range [1, n] and each integer appears once or twice, return an array of all the integers that…

原文链接: https://leetcode-cn.com/problems/string-compression 英文原文Given an array of characters chars, compress it using the following algorithm: Begin with an empty string s. For each group of consecutive repeating characters in chars: If the group's len…

原文链接: https://leetcode-cn.com/problems/add-two-numbers-ii 英文原文You are given two non-empty linked lists representing two non-negative integers. The most significant digit comes first and each of their nodes contains a single digit. Add the two numbers…

原文链接: https://leetcode-cn.com/problems/arithmetic-slices-ii-subsequence 英文原文Given an integer array nums, return the number of all the arithmetic subsequences of nums. A sequence of numbers is called arithmetic if it consists of at least three element…

原文链接: https://leetcode-cn.com/problems/number-of-boomerangs 英文原文You are given n points in the plane that are all distinct, where points[i] = [xi, yi]. A boomerang is a tuple of points (i, j, k) such that the distance between i and j equals the distan…

原文链接: https://leetcode-cn.com/problems/find-all-numbers-disappeared-in-an-array 英文原文Given an array nums of n integers where nums[i] is in the range [1, n], return an array of all the integers in the range [1, n] that do not appear in nums. Example 1:…

原文链接: https://leetcode-cn.com/problems/serialize-and-deserialize-bst 英文原文Serialization is converting a data structure or object into a sequence of bits so that it can be stored in a file or memory buffer, or transmitted across a network connection li…

原文链接: https://leetcode-cn.com/problems/delete-node-in-a-bst 英文原文Given a root node reference of a BST and a key, delete the node with the given key in the BST. Return the root node reference (possibly updated) of the BST. Basically, the deletion can b…

原文链接: https://leetcode-cn.com/problems/sort-characters-by-frequency 英文原文Given a string s, sort it in decreasing order based on the frequency of the characters. The frequency of a character is the number of times it appears in the string. Return the s…