第五周作业——有向图邻接表表示及反向图构造

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1. 有向图中反向图构造。对tinyDG.txt（http://pan.baidu.com/s/1o6jWtcA）文件所表示的图，输出其邻接表表示与反向图的邻接表表示。类名：GraphReverse。博文标题：第五周作业——有向图邻接表表示及反向图构造

邻接表表示示例如下：

0:1 5

2:0 3

……

import java.io.BufferedReader;  import java.io.File;  import java.io.FileReader;  import java.util.ArrayList;  import java.util.LinkedList;  import java.util.List;  import java.util.Queue;  import java.util.Scanner;    public class GraphReverse {     private int vertexNum;     private int arcNum;     private boolean visited[];     private List<ArrayList<Integer>> graphListS;     private List<ArrayList<Integer>> graphListF;     public GraphReverse(int vertexNum,int arcNum,List<ArrayList<Integer>> graphListS,List<ArrayList<Integer>> graphListF){         this.vertexNum=vertexNum;         this.graphListS=graphListS;         visited=new boolean[vertexNum];         this.graphListF=graphListF;     }       public static void main(String[] args) {      String path="f:/tinyDG.txt";      try{          Scanner scanner=new Scanner(new File(path));          List<ArrayList<Integer>> graphListS=new ArrayList<ArrayList<Integer>>();//存储有向图的邻接表          List<ArrayList<Integer>> graphListF=new ArrayList<ArrayList<Integer>>();//存储有向图的反向图的邻接表          int vertexNum=scanner.nextInt();          int arcNum=scanner.nextInt();           for(int i=0;i<vertexNum;i++){               graphListS.add(new ArrayList<Integer>());               graphListF.add(new ArrayList<Integer>());           }           //有向图的存储          for(int i=0;i<arcNum;i++){              int u=scanner.nextInt();              int v=scanner.nextInt();              if(!graphListS.get(u).contains(v)){                  graphListS.get(u).add(v);              }               //有向图的反向图存储              if(!graphListF.get(v).contains(u)){                  graphListF.get(v).add(u);              }                        }          //有向图的广度优先遍历          GraphReverse g1=new GraphReverse(vertexNum, arcNum, graphListS,null);          System.out.println("有向图的邻接表的结果是：");          g1.bfs(vertexNum/2+1,graphListS);         System.out.println(" ");        //有向图的反向图广度优先的遍历          GraphReverse g2=new GraphReverse(vertexNum, arcNum, null,graphListF);          System.out.println("有向图的反向图的邻接表结果是:");          g2.bfs(1,graphListF);                }catch (Exception e) {           e.printStackTrace();      }    }     private  void bfs(int v,List<ArrayList<Integer>> graphList){           Queue<Integer> que = new LinkedList<Integer>();              que.offer(v);          while (!que.isEmpty()) {               v = que.poll();              System.out.print(v+":");               visited[v] = true;               for (int i = 0; i <graphList.get(v).size(); i++) {               int k=graphList.get(v).get(i);              System.out.print(k+" ");             if (!visited[k]){                 //que.add(k);                 que.offer(k);                visited[k] = true;                }               }             System.out.println();         }        }  }

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