2 dfs

import java.io.*;
import java.util.*;

class Graph{
    private int V;
    private LinkedList<Integer>[] adj;
    Graph(int v) {
        V = v;
        adj = new LinkedList[v];
        for (int i = 0; i < v; ++i)
            adj[i] = new LinkedList<>();
    }
    void addEdge(int u, int v) {
        adj[u].add(v);
    }
    void calc(int v, boolean vis[]) {
        vis[v] = true;
        System.out.print(v + " ");
        Iterator<Integer> i = adj[v].listIterator();
        while (i.hasNext()) {
            int n = i.next();
            if (!vis[n])
                calc(n, vis);
        }
    }
    void DFS(int v) {
         boolean vis[] = new boolean[V];
        calc(v, vis);
    }

    public static void main(String args[]) {
        Graph g = new Graph(8);
        g.addEdge(0, 1);
        g.addEdge(3, 2);
        g.addEdge(5, 2);
        g.addEdge(3, 5);
        g.addEdge(3, 4);
        g.addEdge(4, 6);
        g.addEdge(6, 3);
        g.addEdge(6, 7);
        g.addEdge(7, 1);

        System.out.print("DFS traversal from vertex 3 is: ");
        g.DFS(3);
    }
}