邻接表存储图，DFS遍历图的java代码实现

import java.util.*;public class Main{    static int MAX_VERTEXNUM = 100;    static int [] visited = new int[MAX_VERTEXNUM];    public static void main(String [] args){        Graph G = new Graph();        creatGraph(G);        output(G);        for(int i=0;i<G.vertex_num;i++)            visited[i]=0;        System.out.PRintln("DFS遍历的结果是：");        dfs(G,0);//从G.node_list[0]开始DFS遍历    }    static void creatGraph(Graph G){        Scanner in = new Scanner(System.in);        System.out.println("请输入顶点数v和边数e,（v e）:");        G.vertex_num = in.nextInt();        G.edge_num= in.nextInt();        System.out.println("请输入各顶点信息：");        for(int i=0;i<G.vertex_num;i++){            G.node_list[i] = new VertexNode();            G.node_list[i].date = in.next();            G.node_list[i].first_edge = null;  //很重要        }        System.out.println("请输入各边信息(以空格隔开)：");        for(int i=0;i<G.edge_num;i++){            EdgeNode p = new EdgeNode();            String str1 = in.next();            String str2 = in.next();            int v1 = locateVex(G,str1);            int v2 = locateVex(G,str2);            p.vertex = v1;            p.next = G.node_list[v2].first_edge;            G.node_list[v2].first_edge = p;            EdgeNode q = new EdgeNode();//如果是有向图，则不存在下面的代码（上面的代码的存储顺序可能有变化）            q.vertex = v2;            q.next = G.node_list[v1].first_edge;            G.node_list[v1].first_edge = q;        }    }    static int locateVex(Graph G,String s){        for(int i=0;i<G.vertex_num;i++){            if(G.node_list[i].date.equals(s))                return i;        }        return -1;    }    static void output(Graph G){        System.out.println("输出邻接表存储情况：");        EdgeNode p = new EdgeNode();        for(int i=0;i<G.vertex_num;i++){            System.out.print(G.node_list[i].date);            p = G.node_list[i].first_edge;            while(p!=null){                System.out.print("->"+G.node_list[p.vertex].date);                p = p.next;            }            System.out.println();        }    }    static void dfs(Graph G,int k){        System.out.println(G.node_list[k].date);        visited[k]=1;        EdgeNode p = new EdgeNode();        p = G.node_list[k].first_edge;        while(p!=null){            if(visited[p.vertex]!=1)                dfs(G,p.vertex);            p = p.next;        }    }}//顶点存储class VertexNode{    String date;    EdgeNode first_edge = new EdgeNode();}//边存储class EdgeNode{    int vertex;    EdgeNode next;}//图存储class Graph{    VertexNode [] node_list = new VertexNode[100];    int vertex_num,edge_num;}//输出结果：注意：（邻接表的保存顺序与输入边的顺序有关）