DFS.java

import java.io.*;
import java.util.*;
public class DFS{
    private int Vertices; 
    private LinkedList<Integer> adj[];
    @SuppressWarnings("unchecked") DFS(int v){
     Vertices = v;
     adj = new LinkedList[v];
     for (int i = 0; i < v; ++i)
        adj[i] = new LinkedList();
    }
    void addEdge(int v, int w){
        adj[v].add(w); 
    }
    
    void DFS_Util(int v, boolean visited[]){
        visited[v] = true;
        System.out.print(v + " ");
        Iterator<Integer> i = adj[v].listIterator();
        while (i.hasNext()) {
            int n = i.next();
            if (!visited[n])
               DFS_Util(n, visited);
           }
    }
    
    void DFS(int v){
        boolean visited[] = new boolean[Vertices];
        DFS_Util(v, visited);
    }
    
    public static void main(String args[]){
      DFS g = new DFS(8);
      g.addEdge(0, 1);
      g.addEdge(3, 2);
      g.addEdge(3, 4);
      g.addEdge(3, 5);
      g.addEdge(6, 3);
      g.addEdge(6, 7);
      g.addEdge(7, 1);

      System.out.println("DFS order : ");
      g.DFS(3);
    }
}