import java.util.ArrayList;

import java.util.Collection;

import java.util.HashSet;

import java.util.Set;



import com.google.common.collect.ArrayListMultimap;

import com.google.common.collect.Multimap;



public class Graph {

   private static Multimap<Integer,Integer> adjacentDirectedNodesMap = ArrayListMultimap.create();

   private static Set<Integer> alreadyVisited = new HashSet();

   

   static{

      adjacentDirectedNodesMap.put(1, 2);

      adjacentDirectedNodesMap.put(1, 3);

      adjacentDirectedNodesMap.put(1, 5);

      adjacentDirectedNodesMap.put(2, 4);

      adjacentDirectedNodesMap.put(4, 5);

   }

   

   public static void main(String[] args){

      ArrayList visited = new ArrayList();

      

      Integer startNode = 1;

      

      displayAdjacentNodes(startNode);

      

   }

   

   private static void displayAdjacentNodes(Integer integer){

      if(alreadyVisited.contains(integer)){

         return;

      }

      alreadyVisited.add(integer);

      System.out.println(integer);

      for(Integer adjacentNodes: adjacentDirectedNodesMap.get(integer)){

         displayAdjacentNodes(adjacentNodes);

      }

   }

   

}