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转自烟客旅人 sigmainfy — tech-wonderland.net：http://tech-wonderland.net/blog/summary-of-ksum-problems.html Summary for LeetCode 2Sum, 3Sum, 4Sum, K Sum     Overview I summarize vario

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.  开辟一个长为m+n的数组标记每一行每一列是否出现0. 使用O（1）空间方法：使用原数组第一行和第一列记录0 的位置信息 将 0 映射到第一行和第一列，使用col 和row 分别记录第一

典型的二叉搜索问题 先找到在第几行再找第几个 class Solution { public:     bool searchMatrix(vector >& matrix, int target) {         int fir=0,las=matrix.size()-1,le=0,ri=matrix[0].size()-1;         while(fir

leetcode Edit Distance 答案解析 动态规划 Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.) You have the following 3 operations permitted on a word:

Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example, Given n = 3, there are a total of 5 unique BST's.  给一个整数n，求以1~n共能组成多少种二叉搜索树 动态规划题，创建一数组ans

Given n, generate all structurally unique BST's (binary search trees) that store values 1...n. For example, Given n = 3, your program should return all 5 unique BST's shown below. 1

Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the histogram. Above is a histogram where width of

Sliding Window Maximum Given an array nums, there is a sliding window of size k which is moving from the very left of the array to the very right. You can only see the k numbers in the window. Each

题目描述： Write a program to find the n-th ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 1, 2, 3, 4, 5, 6, 8, 9, 10, 12 is the sequence of the