Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors.
Nodes are labeled uniquely.
We use# as a separator for each node, and , as a separator for node label and each neighbor of the node.
As an example, consider the serialized graph {0,1,2#1,2#2,2}.
The graph has a total of three nodes, and therefore contains three parts as separated by #.
0. Connect node 0 to both nodes 1 and 2.1. Connect node 1 to node 2.2. Connect node 2 to node 2 (itself), thus forming a self-cycle.
Visually, the graph looks like the following:
1
/ / 0 --- 2
/ \_/
/** * Definition for undirected graph. * class UndirectedGraphNode { * int label; * List<UndirectedGraphNode> neighbors; * UndirectedGraphNode(int x) { label = x; neighbors = new ArrayList<UndirectedGraphNode>(); } * }; */ public class Solution { private Map<Integer,UndirectedGraphNode> map = new HashMap<Integer,UndirectedGraphNode>(); //深度优先遍历并复制节点 public UndirectedGraphNode DFS_clone(UndirectedGraphNode node) { if(node==null) return null; if(map.containsKey(node.label)) return map.get(node.label); UndirectedGraphNode newNode = new UndirectedGraphNode(node.label); map.put(newNode.label,newNode); for(UndirectedGraphNode N:node.neighbors) { newNode.neighbors.add(DFS_clone(N)); } return newNode; } public UndirectedGraphNode cloneGraph(UndirectedGraphNode node) { return DFS_clone(node); } }
原文：http://www.cnblogs.com/mrpod2g/p/4369824.html