原文链接: https://leetcode-cn.com/problems/tallest-billboard 英文原文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 are give…

原文链接: https://leetcode-cn.com/problems/prison-cells-after-n-days 英文原文There are 8 prison cells in a row and each cell is either occupied or vacant. Each day, whether the cell is occupied or vacant changes according to the following rules: If a cell ha…

原文链接: https://leetcode-cn.com/problems/check-completeness-of-a-binary-tree 英文原文Given the root of a binary tree, determine if it is a complete binary tree. In a complete binary tree, every level, except possibly the last, is completely filled, and all…

原文链接: https://leetcode-cn.com/problems/delete-columns-to-make-sorted-iii 英文原文You are given an array of n strings strs, all of the same length. We may choose any deletion indices, and we delete all the characters in those indices for each string. For …

原文链接: https://leetcode-cn.com/problems/regions-cut-by-slashes 英文原文An n x n grid is composed of 1 x 1 squares where each 1 x 1 square consists of a '/', '\', or blank space ' '. These characters divide the square into contiguous regions. Given the gri…

原文链接: https://leetcode-cn.com/problems/n-repeated-element-in-size-2n-array 英文原文You are given an integer array nums with the following properties: nums.length == 2 * n. nums contains n + 1 unique elements. Exactly one element of nums is repeated n tim…

原文链接: https://leetcode-cn.com/problems/minimum-area-rectangle-ii 英文原文You are given an array of points in the X-Y plane points where points[i] = [xi, yi]. Return the minimum area of any rectangle formed from these points, with sides not necessarily pa…

原文链接: https://leetcode-cn.com/problems/least-operators-to-express-number 英文原文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, …

原文链接: https://leetcode-cn.com/problems/univalued-binary-tree 英文原文A binary tree is uni-valued if every node in the tree has the same value. Given the root of a binary tree, return true if the given tree is uni-valued, or false otherwise. Example 1: In…

原文链接: https://leetcode-cn.com/problems/vowel-spellchecker 英文原文Given a wordlist, we want to implement a spellchecker that converts a query word into a correct word. For a given query word, the spell checker handles two categories of spelling mistakes:…

原文链接: https://leetcode-cn.com/problems/numbers-with-same-consecutive-differences 英文原文Return all non-negative integers of length n such that the absolute difference between every two consecutive digits is k. Note that every number in the answer must n…

原文链接: https://leetcode-cn.com/problems/binary-tree-cameras 英文原文You are given the root of a binary tree. We install cameras on the tree nodes where each camera at a node can monitor its parent, itself, and its immediate children. Return the minimum nu…

原文链接: https://leetcode-cn.com/problems/pancake-sorting 英文原文Given an array of integers arr, sort the array by performing a series of pancake flips. In one pancake flip we do the following steps: Choose an integer k where 1 <= k <= arr.length. Reverse …

原文链接: https://leetcode-cn.com/problems/powerful-integers 英文原文Given three integers x, y, and bound, return a list of all the powerful integers that have a value less than or equal to bound. An integer is powerful if it can be represented as xi + yj fo…

原文链接: https://leetcode-cn.com/problems/equal-rational-numbers 英文原文Given two strings s and t, each of which represents a non-negative rational number, return true if and only if they represent the same number. The strings may use parentheses to denote…

原文链接: https://leetcode-cn.com/problems/flip-binary-tree-to-match-preorder-traversal 英文原文You are given the root of a binary tree with n nodes, where each node is uniquely assigned a value from 1 to n. You are also given a sequence of n values voyage, …

原文链接: https://leetcode-cn.com/problems/k-closest-points-to-origin 英文原文Given an array of points where points[i] = [xi, yi] represents a point on the X-Y plane and an integer k, return the k closest points to the origin (0, 0). The distance between two…

原文链接: https://leetcode-cn.com/problems/subarray-sums-divisible-by-k 英文原文Given an integer array nums and an integer k, return the number of non-empty subarrays that have a sum divisible by k. A subarray is a contiguous part of an array. Example 1: Inp…

原文链接: https://leetcode-cn.com/problems/odd-even-jump 英文原文You are given an integer array arr. 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,…

原文链接: https://leetcode-cn.com/problems/largest-perimeter-triangle 英文原文Given an integer array nums, return the largest perimeter of a triangle with a non-zero area, formed from three of these lengths. If it is impossible to form any triangle of a non-…

原文链接: https://leetcode-cn.com/problems/squares-of-a-sorted-array 英文原文Given an integer array nums sorted in non-decreasing order, return an array of the squares of each number sorted in non-decreasing order. Example 1: Input: nums = [-4,-1,0,3,10] Out…

原文链接: https://leetcode-cn.com/problems/longest-turbulent-subarray 英文原文Given an integer array arr, return the length of a maximum size turbulent subarray of arr. A subarray is turbulent if the comparison sign flips between each adjacent pair of elemen…

原文链接: https://leetcode-cn.com/problems/distribute-coins-in-binary-tree 英文原文You are given the root of a binary tree with n nodes where each node in the tree has node.val coins. There are n coins in total throughout the whole tree. In one move, we may …

原文链接: https://leetcode-cn.com/problems/unique-paths-iii 英文原文You are given an m x n integer array grid where grid[i][j] could be: 1 representing the starting square. There is exactly one starting square. 2 representing the ending square. There is exac…

原文链接: https://leetcode-cn.com/problems/time-based-key-value-store 英文原文Design a time-based key-value data structure that can store multiple values for the same key at different time stamps and retrieve the key's value at a certain timestamp. Implement…

原文链接: https://leetcode-cn.com/problems/triples-with-bitwise-and-equal-to-zero 英文原文Given an integer array nums, return the number of AND triples. An AND triple is a triple of indices (i, j, k) such that: 0 <= i < nums.length 0 <= j < nums.length 0 <= …

原文链接: https://leetcode-cn.com/problems/string-without-aaa-or-bbb 英文原文Given two integers a and b, return any string s such that: s has length a + b and contains exactly a 'a' letters, and exactly b 'b' letters, The substring 'aaa' does not occur in s,…

原文链接: https://leetcode-cn.com/problems/sum-of-even-numbers-after-queries 英文原文You are given an integer array nums and an array queries where queries[i] = [vali, indexi]. For each query i, first, apply nums[indexi] = nums[indexi] + vali, then print the…

原文链接: https://leetcode-cn.com/problems/interval-list-intersections 英文原文You are given two lists of closed intervals, firstList and secondList, where firstList[i] = [starti, endi] and secondList[j] = [startj, endj]. Each list of intervals is pairwise d…

原文链接: https://leetcode-cn.com/problems/vertical-order-traversal-of-a-binary-tree 英文原文Given the root of a binary tree, calculate the vertical order traversal of the binary tree. For each node at position (row, col), its left and right children will be…