using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

    public static bool hasCycle(Node head) {

       if(head == null)

           return false;

       int[] pos = new int[100];

       Node curr = head;

       while(curr.next != null)

       {

          if(pos[curr.data - 1] == 0)

              pos[curr.data - 1] = 1;

          else        

              return true;                 

          curr = curr.next;

       }

       return false;

    }

}

​

public class Node

{

    public int data;

    public Node next;

}