using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        var dateTimeRepresentation = new DateTime(2014,12,29,20,0,0);

        Console.WriteLine(dateTimeRepresentation.ToString("o"));

        dateTimeRepresentation = new DateTime(2015,1,1,6,0,0);

        Console.WriteLine(dateTimeRepresentation.ToString("o"));

    }

}