Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors.
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| public class CloneGraph {
public UndirectedGraphNode cloneGraph(UndirectedGraphNode node) {
if (node == null) {
return null;
}
Queue<UndirectedGraphNode> queue = new LinkedList<UndirectedGraphNode>();
Map<UndirectedGraphNode, UndirectedGraphNode> map = new HashMap<UndirectedGraphNode, UndirectedGraphNode>();
UndirectedGraphNode newHead = new UndirectedGraphNode(node.label);
queue.add(node);
map.put(node, newHead);
while (!queue.isEmpty()) {
UndirectedGraphNode curr = queue.poll();
for (UndirectedGraphNode n : curr.neighbors) {
if (!map.containsKey(n)) {
UndirectedGraphNode copy = new UndirectedGraphNode(n.label);
map.put(n, copy);
queue.add(n);
}
map.get(curr).neighbors.add(map.get(n));
}
}
return newHead;
}
}
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