简单的拓扑排序（POJ2367）

链接：http://poj.org/problem?id=2367

 

代码：

#include <iostream>#include <vector>using namespace std;struct Vertex{vector<int> adjacent;int adjNum;int indegree;Vertex(): indegree(0),adjNum(0){}};struct Graph{vector<Vertex> member;int memNum;Graph():memNum(0){}};Graph G;int topNum[110];void initGraph(){int N;cin >> N;G.memNum = N;for(int i=0;i<N;i++){G.member.push_back(Vertex());}for(int i=0;i<N;i++){int adj;while(cin>>adj && adj!=0){G.member[i].adjNum++;G.member[i].adjacent.push_back(adj-1);G.member[adj-1].indegree++;}}}int findNewVertexOfNoIndegree(){for(int i=0;i<G.memNum;i++){if(G.member[i].indegree == 0){G.member[i].indegree = -1;return i;}}return -1;}void topSort(){int V;for(int i=0;i<G.memNum;i++){V = findNewVertexOfNoIndegree();if(V == -1)break;topNum[i] = V+1;for(int j=0;j<G.member[V].adjNum;j++)G.member[G.member[V].adjacent[j]].indegree--; //this is too ugly, but my time is short}}int main(){initGraph();topSort();for(int i=0;i<G.memNum;i++){cout << topNum[i] << ' ';}cout << endl;return 0;} 

 

简单的拓扑排序伪代码模板：

void Topsort(Graph G){ int Counter; Vertex V, W; for(Counter = 0; Counter < NumVertex; Counter++) { V = FindNewVertexOfIndegreeZero(); if(V == NotAVertex) { Error("Graph has a cycle"); break; } TopNum[V] = Counter; for each W adjacent to V Indegree[W]--; }}