593. 有效的正方形 给定二维空间中四点的坐标,返回四点是否可以构造一个正方形. 一个点的坐标(x,y)由一个有两个整数的整数数组表示. 示例: 输入: p1 = [0,0], p2 = [1,1], p3 = [1,0], p4 = [0,1] 输出: True 注意: 所有输入整数都在 [-10000,10000] 范围内. 一个有效的正方形有四个等长的正长和四个等角(90度角). 输入点没有顺序. class Solution { public boolean validSquare(i…

版权声明: 本文为博主Bravo Yeung(知乎UserName同名)的原创文章,欲转载请先私信获博主允许,转载时请附上网址 http://blog.csdn.net/lzuacm. C#版 - Leetcode 593. 有效的正方形 - 题解 Leetcode 593. Valid Square 在线提交: https://leetcode.com/problems/valid-square/ 题目描述 给定二维空间中四点的坐标,返回四点是否可以构造一个正方形. 一个点的坐标(x, y)由…

Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation. For example: Given "aacecaaa", return "aaacecaaa&qu…

Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Ensure that numbers within the set are sorted in ascending order. Example 1…

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There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites, for example to take course 0 you have to first take course 1, which is expressed as a pair: [0,1] Given the total number of courses and a l…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most k transactions. 解题思路: https://leetcode.com/discuss/18330/is-it-best-solution-with-o-n-o-1…

Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find the minimum element. The array may contain duplicates. 解题思路: 参考Java for LeetCode 081 Search in Rotated Sorted Array II J…