Leetcode 133. Clone Graph-----java

Clone an undirected graph. Each node in the graph contains a and label a lists of its neighbors .

OJ ' s undirected graph serialization:

Nodes is 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 # .

1. First node is labeled as 0 . Connect node to 0 both nodes 1 and 2 .
2. Second node is labeled as 1 . Connect node to 1 node 2 .
3. Third node is labeled as 2 . Connect node 2 to Node 2 (itself), thus forming a self-cycle.

Visually, the graph looks like the following:

       1      /      /       0---2         /          \_/

Copy the diagram. There are two methods of Dfs and BFS, I chose the BFs method.

/*** Definition for undirected graph. * Class Undirectedgraphnode {* int label; * LIST<UNDIRECTEDGRAPHNODE&G T Neighbors; * Undirectedgraphnode (int x) {label = x; neighbors = new arraylist<undirectedgraphnode> ();}}; */ Public classSolution { Publicundirectedgraphnode Clonegraph (Undirectedgraphnode node) {if(node = =NULL )            return NULL; Map Map=NewHashmap<integer,undirectedgraphnode>(); Queue Queue=NewLinkedlist<undirectedgraphnode>();        Queue.add (node); Undirectedgraphnode nnn=NewUndirectedgraphnode (Node.label);        Map.put (NNN.LABEL,NNN);  while( !Queue.isempty ()) {Undirectedgraphnode nn=(Undirectedgraphnode) queue.poll (); List ll1=nn.neighbors; Undirectedgraphnode nn2=(Undirectedgraphnode) map.get (Nn.label); List Ll2=nn2.neighbors;  for(inti = 0;i<ll1.size (); i++) {Undirectedgraphnode Node2=(Undirectedgraphnode) ll1.get (i); if(Map.containskey (Node2.label)) {Ll2.add (Map.get (Node2.label)); }Else{Undirectedgraphnode Node3=NewUndirectedgraphnode (Node2.label);                    Map.put (NODE2.LABEL,NODE3);                    Ll2.add (NODE3);                Queue.add (Node2); }            }        }            returnnnn;}}

Leetcode 133. Clone Graph-----java