using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        var blah = new List<int>() {1,1,1,2,3,4,5,4,4,4};

        var bloh = new HashSet<int>(blah);

        Console.WriteLine(String.Join(",", bloh));

    }

}