Clone an undirected graph. Each node in the graph contains alabeland a list of itsneighbors.
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 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#.
First node is labeled as0. Connect node0to both nodes1and2. Second node is labeled as1. Connect node1to node2. Third node is labeled as2. Connect node2to node2(itself), thus forming a self-cycle.
Visually, the graph looks like the following:
1
/
/
0 --- 2
/
\_/C++
/**
* Definition for undirected graph.
* struct UndirectedGraphNode {
* int label;
* vector<UndirectedGraphNode *> neighbors;
* UndirectedGraphNode(int x) : label(x) {};
* };
*/
class Solution {
public:
UndirectedGraphNode *cloneGraph(UndirectedGraphNode *node){
unordered_map<int, UndirectedGraphNode*> umap;
return clone(node, umap);
}
UndirectedGraphNode *clone(UndirectedGraphNode *node, unordered_map<int, UndirectedGraphNode*> &umap) {
if (!node) return node;
if (umap.count(node->label)) return umap[node->label];
UndirectedGraphNode *newNode = new UndirectedGraphNode(node->label);
umap[node->label] = newNode;
for (int i = 0; i < node->neighbors.size(); ++i){
(newNode->neighbors).push_back(clone(node->neighbors[i],umap));
}
return newNode;
}
};