leetcode:Clone Graph

本文介绍如何使用广度优先搜索(BFS)解决LeetCode中的克隆图问题,通过HashMap记录已访问节点,实现图结构的完全复制。


复制图的结构,直接使用BFS广度优先搜索的方法进行图的遍历

利用HashMap作为是否访问过的标记


<span style="font-size:18px;">/**
 * Definition for undirected graph.
 * class UndirectedGraphNode {
 *     int label;
 *     List<UndirectedGraphNode> neighbors;
 *     UndirectedGraphNode(int x) { label = x; neighbors = new ArrayList<UndirectedGraphNode>(); }
 * };
 */
public class Solution {
    
    
    public UndirectedGraphNode cloneGraph(UndirectedGraphNode node) {
        if(node == null) return node;
        
        HashMap<Integer, UndirectedGraphNode> cloneMap = new HashMap<>();
        UndirectedGraphNode clone = new UndirectedGraphNode(node.label);
        
        LinkedList<UndirectedGraphNode> nodeQueue = new LinkedList<>();
        nodeQueue.add(node);
        
        cloneMap.put(clone.label, clone);
        
        while(!nodeQueue.isEmpty()){
            UndirectedGraphNode top = nodeQueue.pop();
            UndirectedGraphNode cloneTop = cloneMap.get(top.label);
            for(UndirectedGraphNode t : top.neighbors){
                UndirectedGraphNode cloneT = cloneMap.get(t.label);
                if(cloneT == null){
                    cloneT = new UndirectedGraphNode(t.label);
                    cloneMap.put(cloneT.label, cloneT);
                    nodeQueue.push(t);
                }
                cloneTop.neighbors.add(cloneT);
            }
        }
        return clone;
    }
    
}</span>


评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值