using System;

public class Program

{

    private static int _a = 1;

    public static int a {

        get {

            return _a++;

        }

    }

​

    public static void Main()

    {

        if(a == 1 && a == 2 && a == 3)

        {

            Console.WriteLine("Hello World");

        }

        Console.WriteLine(a);

    }

}