克隆图记住:一个map一个queue,照葫芦画瓢BFS 找到一个节点就画一个对应的新的,用map对应,然后添加邻居,记录邻居到queue public UndirectedGraphNode cloneGraph(UndirectedGraphNode node) { if (node==null) return node; UndirectedGraphNode res = new UndirectedGraphNode(node.label); Queue<UndirectedGraphNo…

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…

https://oj.leetcode.com/problems/clone-graph/ 图的拷贝,就是给一个图,再弄出一个一模一样的来. /** * Definition for undirected graph. * struct UndirectedGraphNode { * int label; * vector<UndirectedGraphNode *> neighbors; * UndirectedGraphNode(int x) : label(x) {}; * }; */…

Given an undirected graph, return true if and only if it is bipartite. Recall that a graph is bipartite if we can split it's set of nodes into two independent subsets A and B such that every edge in the graph has one node in A and another node in B.…

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…

Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to check whether these edges make up a valid tree. For example: Given n = 5 and edges = [[0, 1], [0, 2], [0, 3], [1, 4]], return tru…

题目如下:实现克隆图的算法  题目链接 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…

Problem: Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to check whether these edges make up a valid tree. For example: Given n = 5 and edges = [[0, 1], [0, 2], [0, 3], [1, 4]], r…

Given an undirected graph, return true if and only if it is bipartite. Recall that a graph is bipartite if we can split it's set of nodes into two independent subsets A and B such that every edge in the graph has one node in A and another node in B.…

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…

Given n nodes labeled from 0 to n-1 and a list of undirected edges (each edge is a pair of nodes), write a function to check whether these edges make up a valid tree. Example 1: Input: n = 5, and edges = [[0,1], [0,2], [0,3], [1,4]] Output: true Exam…

最近在准备找工作的算法题,刷刷LeetCode,以下是我的解题报告索引,每一题几乎都有详细的说明,供各位码农参考.根据我自己做的进度持续更新中......                              本文地址 LeetCode:Reverse Words in a String LeetCode:Evaluate Reverse Polish Notation LeetCode:Max Points on a Line LeetCode:Sort List LeetCode:Ins…

Note: 后面数字n表明刷的第n + 1遍, 如果题目有**, 表明有待总结 Conclusion questions: [LeetCode] questions conclustion_BFS, DFS LeetCode questions conclustion_Path in Tree [LeetCode] questions conlusion_InOrder, PreOrder, PostOrder traversal [LeetCode] questions for Dynamic…

BFS, DFS 的题目总结. Directed graph: Directed Graph Loop detection and if not have, path to print all path. BFS/DFS: (可以用BFS或者DFS的,主要还是遍历) [LeetCode] 733. Flood Fill_Easy tag: BFS     1 [LeetCode] 690. Employee Importance_Easy tag: BFS    1 [LeetCode] 529…

Here is my collection of solutions to leetcode problems. Related code can be found in this repo: https://github.com/zhuli19901106/leetcode LeetCode - Course Schedule LeetCode - Reverse Linked List LeetCode - Isomorphic Strings LeetCode - Count Primes…

A 2d grid map of m rows and n columns is initially filled with water. We may perform an addLand operation which turns the water at position (row, col) into a land. Given a list of positions to operate, count the number of islands after each addLand o…

https://www.careercup.com/question?id=5103530547347456 Given a list of nodes, each with a left child and a right child (they can be null), determine if all nodes belong in a single valid binary tree. The root is not given. Li家 The solution can be des…

导语 所有的编程练习都在牛客网OJ提交,链接: https://www.nowcoder.com/ta/coding-interviews 九章算法的 lintcode 也有这本书的题目.https://www.lintcode.com/ladder/6/ 第二章 面试需要的基础知识 [面试题3]二维数组中的查找 在一个二维数组中(每个一维数组的长度相同),每一行都按照从左到右递增的顺序排序,每一列都按照从上到下递增的顺序排序.请完成一个函数,输入这样的一个二维数组和一个整数,判断数组中是否含有…

Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to find the number of connected components in an undirected graph. Example 1: 0          3 |          | 1 --- 2    4 Given n = 5 and…

Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to check whether these edges make up a valid tree. For example: Given n = 5 and edges = [[0, 1], [0, 2], [0, 3], [1, 4]], return tru…

原题链接在这里:https://leetcode.com/problems/number-of-connected-components-in-an-undirected-graph/ 题目: Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to find the number of connected com…

Problem link: http://oj.leetcode.com/problems/clone-graph/ This problem is very similar to "Copy List with Random Pointer", we need a hash map to map a node and its clone. The algorithm is 2-pass procedure as follows. CLONE-GRAPH(GraphNode node)…

题目来源: https://leetcode.com/problems/clone-graph/ 题意分析: 克隆一个无向图.每个节点包括一个数值和它的邻居. 题目思路: 直接深度拷贝. 代码(python): # Definition for a undirected graph node # class UndirectedGraphNode(object): # def __init__(self, x): # self.label = x # self.neighbors = [] cl…

Clone Graph题解 原创文章,拒绝转载 题目来源:https://leetcode.com/problems/clone-graph/description/ Description 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 uni…

原题链接在这里:https://leetcode.com/problems/number-of-connected-components-in-an-undirected-graph/ 题目: Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to find the number of connected com…

package Graph; import java.util.ArrayDeque; import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.LinkedList; import java.util.List; import java.util.Map; import java.util.Prior…

题目: 给定无向连通图中一个节点的引用,返回该图的深拷贝(克隆).图中的每个节点都包含它的值 val(Int) 和其邻居的列表(list[Node]). 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…

Starting with an undirected graph (the "original graph") with nodes from 0 to N-1, subdivisions are made to some of the edges. The graph is given as follows: edges[k] is a list of integer pairs (i, j, n) such that (i, j) is an edge of the origin…

Given an undirected graph, return true if and only if it is bipartite. Recall that a graph is bipartite if we can split it's set of nodes into two independent subsets A and B such that every edge in the graph has one node in A and another node in B.…