标签：ref pop 题解 ons visual lint elf tor use
题目：
Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors.
How we serialize an undirected graph:
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 #.
0. Connect node 0 to both nodes 1 and 2.1. Connect node 1 to node 2.2. Connect node 2 to node 2 (itself), thus forming a self-cycle.Visually, the graph looks like the following:
1 / / 0 --- 2 / \_/
Example
return a deep copied graph.
题解：
DFS(recursion)
Solution 1 ()
class Solution { public: unordered_map<UndirectedGraphNode*, UndirectedGraphNode*> hash; UndirectedGraphNode *cloneGraph(UndirectedGraphNode *node) { if (!node) return node; if(hash.find(node) == hash.end()) { hash[node] = new UndirectedGraphNode(node -> label); for (auto neighbor : node -> neighbors) { (hash[node] -> neighbors).push_back( cloneGraph(neighbor) ); } } return hash[node]; } };
DFS(stack)
Solution 2 ()
class Solution { public: UndirectedGraphNode *cloneGraph(UndirectedGraphNode *node) { if (node == nullptr) return nullptr; stack<UndirectedGraphNode* > stack; map<int, UndirectedGraphNode* > visitTable; UndirectedGraphNode* newnode = new UndirectedGraphNode(node->label); visitTable[node->label] = newnode; stack.push(node); while (!stack.empty()) { UndirectedGraphNode* cur = stack.top(); stack.pop(); for (auto neighbor : cur->neighbors) { if (visitTable.find(neighbor->label) == visitTable.end()) { stack.push(neighbor); UndirectedGraphNode* newneighbor = new UndirectedGraphNode(neighbor->label); visitTable[neighbor->label] = newneighbor; } visitTable[cur->label]->neighbors.push_back(visitTable[neighbor->label]); } } return newnode; } };
BFS
Solution 3 ()
class Solution { public: UndirectedGraphNode *cloneGraph(UndirectedGraphNode *node) { if (node == nullptr) return nullptr; queue<UndirectedGraphNode* > queue; map<int, UndirectedGraphNode* > visitTable; UndirectedGraphNode* newnode = new UndirectedGraphNode(node->label); visitTable[node->label] = newnode; queue.push(node); while (!queue.empty()) { UndirectedGraphNode* cur = queue.front(); queue.pop(); for (auto neighbor : cur->neighbors) { if (visitTable.find(neighbor->label) == visitTable.end()) { UndirectedGraphNode* newneighbor = new UndirectedGraphNode(neighbor->label); visitTable[neighbor->label] = newneighbor; queue.push(neighbor); } visitTable[cur->label]->neighbors.push_back(visitTable[neighbor->label]); } } return newnode; } };
标签：ref pop 题解 ons visual lint elf tor use
原文地址：http://www.cnblogs.com/Atanisi/p/6858793.html
