133. 克隆图 给你无向 连通 图中一个节点的引用,请你返回该图的 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]). class Node { public int val; public List<Node> neighbors; } 测试用例格式: 简单起见,每个节点的值都和它的索引相同.例如,第一个节点值为 1,第二个节点值为 2,以此类推.该图在测试用例中使用邻接列表表示. 邻接列表是用于表示有限图的无序列表的集合.每个列表都描…

克隆图 克隆一张无向图,图中的每个节点包含一个 label (标签)和一个 neighbors (邻接点)列表 . OJ的无向图序列化: 节点被唯一标记. 我们用 # 作为每个节点的分隔符,用 , 作为节点标签和邻接点的分隔符. 例如,序列化无向图 {0,1,2#1,2#2,2}. 该图总共有三个节点, 被两个分隔符  # 分为三部分. 第一个节点的标签为 0,存在从节点 0 到节点 1 和节点 2 的两条边. 第二个节点的标签为 1,存在从节点 1 到节点 2 的一条边. 第三个节点的标签为…

方法一:dfs(递归) map<Node*,Node*> dict; Node* clone(Node* node) { if (!node) return node; if (dict.count(node)) return dict[node]; dict[node]=new Node(node->val,vector<Node*>{}); // 这里不能写clone(node),会导致死循环,记住,在new的时候千万不要再递归,递归最低层一定有一个明确结果,所以要把截止…

Leetcode之广度优先搜索(BFS)专题-133. 克隆图(Clone Graph) BFS入门详解:Leetcode之广度优先搜索(BFS)专题-429. N叉树的层序遍历(N-ary Tree Level Order Traversal) 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]). 示例: 输入: {"$id":"1","neighbors&quo…

133. 克隆图 知识点:图:递归;BFS 题目描述 给你无向 连通 图中一个节点的引用,请你返回该图的 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]). class Node { public int val; public List<Node> neighbors; } 示例 输入:adjList = [[2,4],[1,3],[2,4],[1,3]] 输出:[[2,4],[1,3],[2,4],[1,3]] 解释: 图中有 4 个节…

[问题]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]). 解释: 节点 的值是 ,它有两个邻居:节点 和 . 节点 的值是 ,它有两个邻居:节点 和 . 节点 的值是 ,它有两个邻居:节点 和 . 节点 的值是 ,它有两个邻居:节点 和 . 提示: 节点数介于 1 到 100 之间. 无向图是一个简单图,这意味着图中没有重复的边,也没有自环. 由于图是无向的,如果节点 p 是节点 q 的邻居,那么节点…

［抄题］: 克隆一张无向图,图中的每个节点包含一个 label 和一个列表 neighbors. ［思维问题］: ［一句话思路］: 先BFS克隆点(一个点+扩展所有邻居),再克隆邻居(一个点+扩展所有邻居). ［输入量］:空: 正常情况:特大:特小:程序里处理到的特殊情况:异常情况(不合法不合理的输入): ［画图］: ［一刷］: bfs的结果应该存在一个节点构成的数组中ArrayList<UndirectedGraphNode>,作为for(UndirectedGraphNode n: nod…

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 neighb…

A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null. Return a deep copy of the list. 解题思路: 我们在Java for LeetCode 133 Clone Graph题中做过图的复制,本题和图的复制十分类似,JAVA实现如下: public Random…

图篇 # 题名 刷题 通过率 难度 133 克隆图   18.7% 中等 207 课程表   40.0% 中等 210 课程表 II   40.0% 中等 310 最小高度树   29.5% 中等 332 重新安排行程   23.9% 中等 399 除法求值   38.5% 中等 684 冗余连接   42.3% 中等 685 冗余连接 II   21.2% 困难 743 网络延迟时间   33.0% 中等 765 情侣牵手   48.4% 困难 785 判断二分图   30.5% 中等 802…

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…

假如说你想复制一个简单变量.很简单: int apples = 5; int pears = apples; 不仅仅是int类型,其它七种原始数据类型(boolean,char,byte,short,float,double.long)同样适用于该类情况. 但是如果你复制的是一个对象,情况就有些复杂了. 假设说我是一个beginner,我会这样写: class Student { private int number; public int getNumber() { return number…

文章转载自https://www.cnblogs.com/Qian123/p/5710533.html 阅读目录 为什么要克隆? 如何实现克隆 浅克隆和深克隆 解决多层克隆问题 总结 假如说你想复制一个简单变量.很简单: int apples = 5; int pears = apples; 不仅仅是int类型,其它七种原始数据类型(boolean,char,byte,short,float,double.long)同样适用于该类情况. 但是如果你复制的是一个对象,情况就有些复杂了. 假设说我是…

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]).示例: 输入:{"$id":"1","neighbors":[{"$id":"2","neighbors":[{"$ref":"1"},{"$id":"3",&quo…

Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Ensure that numbers within the set are sorted in ascending order. Example 1…

Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation. For example: Given "aacecaaa", return "aaacecaaa&qu…

Given a 2D board and a list of words from the dictionary, find all words in the board. Each word must be constructed from letters of sequentially adjacent cell, where "adjacent" cells are those horizontally or vertically neighboring. The same le…

Design a data structure that supports the following two operations: void addWord(word)bool search(word) search(word) can search a literal word or a regular expression string containing only letters a-z or .. A . means it can represent any one letter.…

There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites, for example to take course 0 you have to first take course 1, which is expressed as a pair: [0,1] Given the total number of courses and a l…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most k transactions. 解题思路: https://leetcode.com/discuss/18330/is-it-best-solution-with-o-n-o-1…

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. The array may contain duplicates. 解题思路: 参考Java for LeetCode 081 Search in Rotated Sorted Array II J…

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 duplicate exists in the array. 解题思路: 本题和Java for LeetCode 033 Search in Rotated S…

The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order, We get the following sequence (ie, for n = 3): "123" "132" "213" "231" "312" "…

Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order. For example, Given n = 3, You should return the following matrix: [ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ]] 解题思路: 参考Java for LeetCode 054 Spiral Matrix,修改下…

Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary). You may assume that the intervals were initially sorted according to their start times. Example 1: Given intervals [1,3],[6,9], insert and merge…

Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Determine if you are able to reach the last index. For example: A =…

Given a collection of numbers that might contain duplicates, return all possible unique permutations. For example, [1,1,2] have the following unique permutations: [1,1,2], [1,2,1], and [2,1,1]. 解题思路一: 发现Java for LeetCode 046 Permutations自己想多了,代码直接拿来用…

Implement wildcard pattern matching with support for '?' and '*'. '?' Matches any single character. '*' Matches any sequence of characters (including the empty sequence). The matching should cover the entire input string (not partial). The function p…

Given a string containing just the characters '(' and ')', find the length of the longest valid (well-formed) parentheses substring. For "(()", the longest valid parentheses substring is "()", which has length = 2. Another example is &…