拓扑排序java语言

import java.util.Stack; public class TopologicalSort { int[][] graph; int[] list; void input(int[][] graph) { this.graph=graph; list=new int[graph.length]; calculate(); } void calculate() { Stack<Integer> stack=new Stack<Integer>(); for(int i=0; i<graph.length; i++){ if(graph[i][0]==0){ stack.push(i); } } int i=0; while(stack.empty()!=true){ list[i]=(Integer)stack.pop(); for(int j=1; j<graph[list[i]].length; j++){ int k=graph[list[i]][j]; if((--graph[k][0])==0){ stack.push(k); } } i++; } if(i<graph.length){ System.out.println("存在环，不可排序！"); System.exit(0); } } int[] getList() { return list; } }