Clone GraphClone an undirected graph. Each node in the graph contains a label and a list of its neighbors. OJ's undirected graph serialization:Nodes are labeled uniquely. We use # as a separator for each node, and , as a separator for node label and…

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 DFS BFS 日期 题目地址:https://leetcode.com/problems/clone-graph/ 题目描述 Given a reference of a node in a connected undirected graph, return a deep copy (clone) of the graph. Each node…

Combination Sum Combination Sum Total Accepted: 25850 Total Submissions: 96391 My Submissions Question Solution Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. The…

全排列问题.经常使用的排列生成算法有序数法.字典序法.换位法(Johnson(Johnson-Trotter).轮转法以及Shift cursor cursor* (Gao & Wang)法. [题目] Given a collection of numbers, return all possible permutations. For example, [1,2,3] have the following permutations: [1,2,3], [1,3,2], [2,1,3], [2…

以前从来没有写过解题报告,只是看到大肥羊河delta写过不少.最近想把写博客的节奏给带起来,所以就挑一个比较容易的题目练练手. 原题链接 https://leetcode.com/problems/course-schedule/ 题目大意 有n个课程,编号分别是0到n-1.我们的目标是修完所有课程.然而有些课程有前置课程的,我们必须修完前置课程才能修该门课程.题目给了我们课程之间的前置关系,让我们判断是否能修完所有课程. 题目原型 这个题目的描述简单粗暴,我们不难发现,其实是给了我们一个有向图…

Sort ColorsGiven an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue. Here, we will use the integers 0, 1, and 2 to represent the color red, wh…

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 并查集 日期 题目地址:https://leetcode-cn.com/problems/number-of-connected-components-in-an-undirected-graph/ 题目描述 Given n nodes labeled from 0 to n - 1 and a list of undirected edges (ea…

Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors. OJ's undirected graph serialization: Nodes are labeled uniquely. We use # as a separator for each node, and , as a separator for node label and each neigh…

Given a reference of a node in a connected undirected graph, return a deep copy (clone) of the graph. Each node in the graph contains a val (int) and a list (List[Node]) of its neighbors. Example: Input: {"$id":"1","neighbors"…

原题地址:https://oj.leetcode.com/problems/clone-graph/ 题意:实现对一个图的深拷贝. 解题思路:由于遍历一个图有两种方式:bfs和dfs.所以深拷贝一个图也可以采用这两种方法.不管使用dfs还是bfs都需要一个哈希表map来存储原图中的节点和新图中的节点的一一映射.map的作用在于替代bfs和dfs中的visit数组,一旦map中出现了映射关系,就说明已经复制完成,也就是已经访问过了. dfs代码: # Definition for a undire…