package y2019.Algorithm.array; /** * @ProjectName: cutter-point * @Package: y2019.Algorithm.array * @ClassName: Transpose * @Author: xiaof * @Description: 867. Transpose Matrix * * Given a matrix A, return the transpose of A. * The transpose of a mat…

package y2019.Algorithm.array; /** * @ProjectName: cutter-point * @Package: y2019.Algorithm.array * @ClassName: IsToeplitzMatrix * @Author: xiaof * @Description: 766. Toeplitz Matrix * A matrix is Toeplitz if every diagonal from top-left to bottom-ri…

package y2019.Algorithm.array; import java.util.Arrays; import java.util.Stack; /** * @ClassName Rotate * @Description TODO 189. Rotate Array * * Given an array, rotate the array to the right by k steps, where k is non-negative. * * Input: [1,2,3,4,5…

题目等级:Easy 题目描述: Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward. Example 1: Input: 121 Output: true Example 2: Input: -121 Output: false Explanation: From left to right, it reads -12…

题目等级:4Sum II(Medium) 题目描述: Given four lists A, B, C, D of integer values, compute how many tuples (i, j, k, l) there are such that A[i] + B[j] + C[k] + D[l] is zero. To make problem a bit easier, all A, B, C, D have same length of N where 0 ≤ N ≤ 500…

题目等级:4Sum(Medium) 题目描述: Given an array nums of n integers and an integer target, are there elements a, b, c, and d in nums such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target. Note: The solution se…

题目等级:3Sum(Medium) 题目描述: Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Note: The solution set must not contain duplicate triplets. Exam…

Best Time to Buy and Sell Stock with Transaction Fee 题目等级:Medium 题目描述: Your are given an array of integers prices, for which the i-th element is the price of a given stock on day i; and a non-negative integer fee representing a transaction fee. You m…

Difficulty:medium  More:[目录]LeetCode Java实现 Description https://leetcode.com/problems/rotate-image/ You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note: You have to rotate the image in-place, which…

Difficulty:medium  More:[目录]LeetCode Java实现 Description Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first integer of each…

题目等级:Hard 题目描述:   There are two sorted arrays nums1 and nums2 of size m and n respectively.   Find the median of the two sorted arrays. The overall run time complexity should be O(log (m+n)).   You may assume nums1 and nums2 cannot be both empty.   E…

Rotate Image You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Follow up: Could you do this in-place? 最简单的想法,两重循环. 第一重循环是对于矩阵的层次(从外到内) 第二重循环是对于每一层次的四元素轮换 举例: 1 2 3 4 5 6 7 8 9 最外层: 1-->3-->9-->7 2…

题目等级:Medium 题目描述:   You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.   You may…

package y2019.Algorithm.array.medium; import java.util.*; /** * @ProjectName: cutter-point * @Package: y2019.Algorithm.array.medium * @ClassName: CombinationSum * @Author: xiaof * @Description: TODO 39. Combination Sum * Given a set of candidate numb…

题目等级:Easy 题目描述: Given a 32-bit signed integer, reverse digits of an integer. Example 1: Input: 123 Output: 321 Example 2: Input: -123 Output: -321 Example 3: Input: 120 Output: 21    题意:给出一个 32 位的有符号整数,你需要将这个整数中每位上的数字进行反转. 解题思路:   本题很简单,我们给出以下两种方法.  …

package y2019.Algorithm.dynamicprogramming.hard; /** * @Auther: xiaof * @Date: 2019/12/11 08:59 * @Description: 1278. 分割回文串 III * * 给你一个由小写字母组成的字符串 s,和一个整数 k. * 请你按下面的要求分割字符串: * 首先,你可以将 s 中的部分字符修改为其他的小写英文字母. * 接着,你需要把 s 分割成 k 个非空且不相交的子串,并且每个子串都是回文串.…

package y2019.Algorithm.dynamicprogramming.easy; /** * @ProjectName: cutter-point * @Package: y2019.Algorithm.dynamicprogramming.easy * @ClassName: Rob * @Author: xiaof * @Description: 198. House Robber * You are a professional robber planning to rob…

这几天一直再想这样刷题真的有必要么,这种单纯的刷题刷得到尽头么??? 这种出题的的题目是无限的随便百度,要多少题有多少题,那么我这一直刷的意义在哪里??? 最近一直苦苦思考,不明所以,刷题刷得更多的感受是机械化的操作. 抽空看了以前乔布斯的演讲有点感受,经过几天的思考最终我想通了. 这里刷题是对自己思考方式的提炼,这种题写多了对自己编码的思维方式有所提升这个是无形的. 其次我没必要去这么刷题,因为题目无限,时间有限,所以应该做的是去品味每一道题,思考如果以后遇到同类的题,我应该从一个什么样的角度…

package y2019.Algorithm.array.medium; /** * @ProjectName: cutter-point * @Package: y2019.Algorithm.array.medium * @ClassName: SortColors * @Author: xiaof * @Description: TODO 75. Sort Colors * Given an array with n objects colored red, white or blue,…

package y2019.Algorithm.array; /** * @ProjectName: cutter-point * @Package: y2019.Algorithm.array * @ClassName: IsOneBitCharacter * @Author: xiaof * @Description: TODO 717. 1-bit and 2-bit Characters * We have two special characters. The first charac…

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/search-a-2d-matrix/description/ 题目描述 Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the follow…

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 左下或者右上开始查找 顺序查找 库函数 日期 题目地址:https://leetcode.com/problems/search-a-2d-matrix/description/ 题目描述 Write an efficient algorithm that searches for a value in an m x n matrix. This m…

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/rotate-image/description/ 题目描述 You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note: Y…

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/score-after-flipping-matrix/description/ 题目描述 We have a two dimensional matrix A where each value is 0 or 1. A move consists of choosing a…

Search a 2D Matrix II Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted in ascending from left to right. Integers in each column are sorted in ascendin…

题目等级:Medium 题目描述:   Given a string, find the length of the longest substring without repeating characters.   Example 1: Input: "abcabcbb" Output: 3 Explanation: The answer is "abc", with the length of 3.   Example 2: Input: "bbbbb…

说实话,这道题我没想出来,但是看解题报告题解比较让人觉得眼前一亮,这里记录下来 package y2019.Algorithm.greedy.medium; import java.util.Arrays; import java.util.LinkedList; /** * @Auther: xiaof * @Date: 2019/12/19 09:05 * @Description: 406. 根据身高重建队列 * * 假设有打乱顺序的一群人站成一个队列. 每个人由一个整数对(h, k)表示…

简单粗暴,代码有待优化,不过自己独立完成,没有参考任何材料,还是比较满意的 package y2019.Algorithm.stack.medium; import java.util.Stack; /** * @Auther: xiaof * @Date: 2019/12/6 09:06 * @Description:331. 验证二叉树的前序序列化 * * 序列化二叉树的一种方法是使用前序遍历.当我们遇到一个非空节点时,我们可以记录下这个节点的值.如果它是一个空节点, * 我们可以使用一个标…

最近做leetcode总感觉自己是个智障,基本很少有题能自己独立做出来,都是百度... 不过终于还是做出了一题...而且速度效率还可以 哎,加油吧,尽量锤炼自己 package y2019.Algorithm.str.medium; import java.util.ArrayList; import java.util.List; /** * @Auther: xiaof * @Date: 2019/11/21 09:00 * @Description: 1023. Camelcase Mat…

我被这些题整哭了,你呢??? 日了狗啊...... 好难啊.... 按照这个样子搞,不用找工作了,回家放牛去....... package y2019.Algorithm.divideandconquer.medium; /** * @ProjectName: cutter-point * @Package: y2019.Algorithm.divideandconquer.medium * @ClassName: FindKthLargest * @Author: xiaof * @Descr…