题目如下: Given a m x n binary matrix mat. In one step, you can choose one cell and flip it and all the four neighbours of it if they exist (Flip is changing 1 to 0 and 0 to 1). A pair of cells are called neighboors if they share one edge. Return the min…

给一个矩阵mat,每个格子都是0或1,翻转一个格子会将该格子以及相邻的格子(有共同边)全部翻转(0变为1,1变为0) 求问最少需要翻转几次将所有格子全部置为0. 这题的重点是数据范围,比赛结束看了眼数据范围想把自己锤死= = m == mat.length n == mat[0].length 1 <= m <= 3 1 <= n <= 3 mat[i][j] is 0 or 1.   也就是....最多也就9个格子.....暴力怎么都能搞出来的.....   首先分析每个格子要么…

[LeetCode]452. Minimum Number of Arrows to Burst Balloons 解题报告(Python) 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/description/ 题目描述: There are a number of spherical balloons spread in two-dimensio…

题目如下: In an array A containing only 0s and 1s, a K-bit flip consists of choosing a (contiguous) subarray of length K and simultaneously changing every 0 in the subarray to 1, and every 1 in the subarray to 0. Return the minimum number of K-bit flips…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 贪心算法 日期 题目地址:https://leetcode.com/problems/minimum-number-of-refueling-stops/ 题目描述 A car travels from a starting position to a destination which is target miles east of the sta…

题目如下: 解题思路:本题可以采用贪心算法.首先把balloons数组按end从小到大排序,然后让第一个arrow的值等于第一个元素的end,依次遍历数组,如果arrow不在当前元素的start到end的区间,表示这个arrow不能刺破气球,arrow总数加一,然后令arrow继续等于当前这个元素的end,直到数组遍历完成. 代码如下: class Solution(object): def findMinArrowShots(self, points): """ :type…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 遍历数字+质数判断 日期 题目地址:https://leetcode.com/problems/prime-number-of-set-bits-in-binary-representation/description/ 题目描述 Given two integers L and R, find the count of numbers in the…

题目如下: Given a set of points in the xy-plane, determine the minimum area of any rectangle formed from these points, with sides not necessarily parallel to the x and y axes. If there isn't any rectangle, return 0. Example 1: Input: [[1,2],[2,1],[1,0],[…

[LeetCode]375. Guess Number Higher or Lower II 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址: https://leetcode.com/problems/guess-number-higher-or-lower-ii/description/ 题目描述: We are playing the Guess Game. The game is as f…

[LeetCode]137. Single Number II 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/single-number-ii/description/ 题目描述: Given an array of integers, every element appears three times except for one, which appears exactly once. Find that singl…

[LeetCode]306. Additive Number 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.me/ 题目地址:https://leetcode.com/problems/additive-number/description/ 题目描述: Additive number is a string whose digits can form additive se…

题目如下: 解题思路:本题和[leetcode]583. Delete Operation for Two Strings 类似,区别在于word1[i] != word2[j]的时候,是删除word1[i]还是word2[j]取决于min(dp[i-1][j]+ord(word1[i-1]),dp[i][j-1]+ord(word2[j-1])). 代码如下: class Solution(object): def minimumDeleteSum(self, s1, s2): ""…

Difficulty: Hard  More:[目录]LeetCode Java实现 Description Validate if a given string can be interpreted as a decimal number. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10&qu…

今天看到LeetCode OJ题目下方多了"Show Tags"功能.我觉着挺好,方便刚開始学习的人分类练习.同一时候也是解题时的思路提示. [题目] 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. You may assume no…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 方法一:模拟过程 方法二:求和-n*最小值 方法三:排序 日期 [LeetCode] 题目地址:https://leetcode.com/problems/minimum-moves-to-equal-array-elements/ Difficulty: Easy 题目描述 Given a non-empty integer array of si…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 遍历一遍 日期 题目地址:https://leetcode.com/problems/minimum-domino-rotations-for-equal-row/ 题目描述 In a row of dominoes, A[i] and B[i] represent the top and bottom halves of the i-th domi…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 动态规划 参考资料 日期 题目地址:https://leetcode.com/problems/minimum-swaps-to-make-sequences-increasing/description/ 题目描述 We have two integer sequences A and B of the same non-zero length.…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址: https://leetcode.com/problems/minimum-add-to-make-parentheses-valid/ 题目描述 Given a string S of '(' and ')' parentheses, we add the minimum number of parentheses ( '(' o…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址: https://leetcode.com/problems/minimum-genetic-mutation/description/ 题目描述 A gene string can be represented by an 8-character long string, with choices from "A", &q…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 方法一:排序 方法二:直接找中位数 日期 题目地址:https://leetcode.com/problems/minimum-moves-to-equal-array-elements-ii/description/ 题目描述 Given a non-empty integer array, find the minimum number of m…

Given a non-empty integer array, find the minimum number of moves required to make all array elements equal, where a move is incrementing a selected element by 1 or decrementing a selected element by 1. You may assume the array's length is at most 10…

题目如下: 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 valid and return any valid string. Formally, a…

题目如下: You are given two strings s1 and s2 of equal length consisting of letters "x" and "y" only. Your task is to make these two strings equal to each other. You can swap any two characters that belong to different strings, which means…

题目如下: We have two integer sequences A and B of the same non-zero length. We are allowed to swap elements A[i] and B[i].  Note that both elements are in the same index position in their respective sequences. At the end of some number of swaps, A and B…

题目如下: In an n*n grid, there is a snake that spans 2 cells and starts moving from the top left corner at (0, 0)and (0, 1). The grid has empty cells represented by zeros and blocked cells represented by ones. The snake wants to reach the lower right co…

题目: You are standing at position 0 on an infinite number line. There is a goal at position target. On each move, you can either go left or right. During the n-th move (starting from 1), you take n steps. Return the minimum number of steps required to…

题目如下: In a row of dominoes, A[i] and B[i] represent the top and bottom halves of the i-th domino.  (A domino is a tile with two numbers from 1 to 6 - one on each half of the tile.) We may rotate the i-th domino, so that A[i] and B[i] swap values. Ret…

题目如下: In a country popular for train travel, you have planned some train travelling one year in advance.  The days of the year that you will travel is given as an array days.  Each day is an integer from 1 to 365. Train tickets are sold in 3 differen…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 滑动窗口 日期 题目地址:https://leetcode-cn.com/problems/minimum-swaps-to-group-all-1s-together/ 题目描述 Given a binary array data, return the minimum number of swaps required to group all 1'…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 Java解法 Python解法 日期 题目地址:https://leetcode.com/problems/minimum-absolute-difference-in-bst/#/description 题目描述 Given a binary search tree with non-negative values, find the minimu…