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
/ \
\_/