[LeetCode][JavaScript]Clone Graph
Clone Graph
Clone an undirected graph. Each node in the graph contains a label
and a list of its neighbors
.
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 as
0
. Connect node0
to both nodes1
and2
. - Second node is labeled as
1
. Connect node1
to node2
. - Third node is labeled as
2
. Connect node2
to node2
(itself), thus forming a self-cycle.
Visually, the graph looks like the following:
1 / \ / \ 0 --- 2 / \ \_/
https://leetcode.com/problems/clone-graph/
节点是唯一的,就是要注意像例子中这样从2到2的环,有个test case是{0,0,0}
DFS递归解法:
1 /** 2 * Definition for undirected graph. 3 * function UndirectedGraphNode(label) { 4 * this.label = label; 5 * this.neighbors = []; // Array of UndirectedGraphNode 6 * } 7 */ 8 /** 9 * @param {UndirectedGraphNode} graph 10 * @return {UndirectedGraphNode} 11 */ 12 var cloneGraph = function(graph) { 13 var visited = {}; 14 if(graph === null){ 15 return null; 16 }else{ 17 return dfs(graph); 18 } 19 20 function dfs(node){ 21 var newNode = null; 22 if(visited[node.label]){ 23 newNode = visited[node.label]; 24 }else{ 25 newNode = new UndirectedGraphNode(node.label); 26 visited[node.label] = newNode; 27 } 28 for(var i = 0; i < node.neighbors.length; i++){ 29 if(node.neighbors[i].label !== node.label){ 30 if(!visited[node.neighbors[i].label]){ 31 newNode.neighbors.push(dfs(node.neighbors[i])); 32 }else{ 33 newNode.neighbors.push(visited[node.neighbors[i].label]); 34 } 35 }else{ 36 newNode.neighbors.push(visited[node.label]); 37 } 38 } 39 return newNode; 40 } 41 };
BFS非递归解法:
1 /** 2 * Definition for undirected graph. 3 * function UndirectedGraphNode(label) { 4 * this.label = label; 5 * this.neighbors = []; // Array of UndirectedGraphNode 6 * } 7 */ 8 9 /** 10 * @param {UndirectedGraphNode} graph 11 * @return {UndirectedGraphNode} 12 */ 13 var cloneGraph = function(graph) { 14 var visited = {}; 15 var queue = []; 16 if(graph === null){ 17 return null; 18 }else{ 19 visited[graph.label] = new UndirectedGraphNode(graph.label); 20 queue.push(graph); 21 bfs(); 22 return visited[graph.label]; 23 } 24 25 function bfs(){ 26 while(queue.length > 0){ 27 var node = queue.shift(); 28 var newNode = visited[node.label]; 29 for(var i = 0; i < node.neighbors.length; i++){ 30 if(node.neighbors[i].label !== node.label){ 31 var neighbor = node.neighbors[i]; 32 var newNeighbor = null; 33 if(!visited[neighbor.label]){ 34 newNeighbor = new UndirectedGraphNode(neighbor.label); 35 visited[neighbor.label] = newNeighbor; 36 queue.push(neighbor); 37 }else{ 38 newNeighbor = visited[neighbor.label]; 39 } 40 newNode.neighbors.push(newNeighbor); 41 }else{ 42 newNode.neighbors.push(visited[node.label]); 43 } 44 } 45 } 46 } 47 };