贴一个小弟我写的找出有向图中所有环的算法

贴一个我写的找出有向图中所有环的算法
最近有需要就在网上找了找求有向图中环的算法,结果发现大多思路都很混乱.
于是乎自己写了下贴出来,大家有兴趣可以看看.

Java code

import java.util.ArrayList;public class Test7 {    static private int[] visited={0,0,0,0,0,0,0};//7个节点,0为未访问    static private int[][] e={                            {0,1,1,0,0,0,0},                            {0,0,1,1,0,0,0},                            {0,0,0,0,0,1,0},                            {0,0,0,0,1,0,0},                            {0,0,0,0,0,0,0},                            {0,0,0,0,0,0,1},                            {1,0,0,0,0,0,0}};//邻接矩阵,值大家任意改.    static ArrayList<Integer> trace=new ArrayList<Integer>();//从出发节点到当前节点的轨迹    static boolean hasCycle=false;    public static void main(String[] args) {        findCycle(0);        if(!hasCycle)             System.out.println("No Cycle.");    }    static void findCycle(int v)   //递归DFS    {        if(visited[v]==1)        {            int j;            if((j=trace.indexOf(v))!=-1)            {                hasCycle=true;                System.out.print("Cycle:");                while(j<trace.size())                {                    System.out.print(trace.get(j)+" ");                    j++;                }                System.out.print("\n");                return;            }            return;        }        visited[v]=1;        trace.add(v);                for(int i=0;i<7;i++)        {            if(e[v][i]==1)                findCycle(i);        }        trace.remove(trace.size()-1);    }}