[LeetCode] 997. Find the Town Judge In a town, there are n people labeled from 1 to n. There is a rumor that one of these people is secretly the town judge. If the town judge exists, then:The town judge trusts nobody.Everybody (except f 2020-05-11 #leetcode #hashmap #java #graph
[LeetCode] 1249. Minimum Remove to Make Valid Parentheses Given a string s of ‘(‘ , ‘)’ and lowercase English characters. Your task is to remove the minimum number of parentheses ( ‘(‘ or ‘)’, in any positions ) so that the resulting parentheses string is va 2020-05-08 #leetcode #java #string #stack
[LeetCode] 84. Largest Rectangle in Histogram Given an array of integers heights representing the histogram’s bar height where the width of each bar is 1, return the area of the largest rectangle in the histogram. Example 1:Input: heights = 2020-05-08 #leetcode #array #java #javascript #stack #monotonic stack
[LeetCode] 993. Cousins in Binary Tree Given the root of a binary tree with unique values and the values of two different nodes of the tree x and y, return true if the nodes corresponding to the values x and y in the tree are cousins, or f 2020-05-08 #leetcode #java #tree #bfs #dfs
[LeetCode] 443. String Compression 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 length is 1, appe 2020-05-08 #leetcode #two pointer #java #string #simulation
[LeetCode] 130. Surrounded Regions You are given an m x n matrix board containing letters ‘X’ and ‘O’, capture regions that are surrounded: Connect: A cell is connected to adjacent cells horizontally or vertically.Region: To form a reg 2020-05-02 #leetcode #array #java #bfs #dfs #matrix
[LeetCode] 1095. Find in Mountain Array (This problem is an interactive problem.) You may recall that an array arr is a mountain array if and only if: arr.length >= 3There exists some i with 0 < i < arr.length - 1 such that:ar 2020-04-29 #leetcode #array #java #binary search
[LeetCode] 704. Binary Search Given an array of integers nums which is sorted in ascending order, and an integer target, write a function to search target in nums. If target exists, then return its index. Otherwise, return -1. You 2020-04-29 #leetcode #java #javascript #binary search
[LeetCode] 221. Maximal Square Given an m x n binary matrix filled with 0’s and 1’s, find the largest square containing only 1’s and return its area. Example 1: Input: matrix = [[“1”,”0”,”1”,”0”,”0”],[“1”,”0”,”1”,”1”,”1”],[“1” 2020-04-28 #leetcode #java #dynamic programming #matrix
[LeetCode] 621. Task Scheduler You are given an array of CPU tasks, each represented by letters A to Z, and a cooling time, n. Each cycle or interval allows the completion of one task. Tasks can be completed in any order, but there 2020-04-26 #leetcode #hashmap #java #greedy #heap