using System.Globalization;

public class MainClass {

    public static void Main(string[] args)  {

        DateTime dt = DateTime.Now;

        String[] format = {

            "d", "D",

            "f", "F",

            "g", "G",

            "m",

            "r",

            "s",

            "t", "T",

            "u", "U",

            "y",

            "dddd, MMMM dd yyyy",

            "ddd, MMM d \"'\"yy",

            "dddd, MMMM dd",

            "M/yy",

            "dd-MM-yy",

        };

        String date;

        for (int i = 0; i < format.Length; i++) {

            date = dt.ToString(format[i], DateTimeFormatInfo.InvariantInfo);

            Console.WriteLine(String.Concat(format[i], " :" , date));

        }

   /** Output.

    *

    * d :08/17/2000

    * D :Thursday, August 17, 2000

    * f :Thursday, August 17, 2000 16:32

    * F :Thursday, August 17, 2000 16:32:32

    * g :08/17/2000 16:32

    * G :08/17/2000 16:32:32

    * m :August 17

    * r :Thu, 17 Aug 2000 23:32:32 GMT

    * s :2000-08-17T16:32:32

    * t :16:32

    * T :16:32:32

    * u :2000-08-17 23:32:32Z

    * U :Thursday, August 17, 2000 23:32:32

    * y :August, 2000

    * dddd, MMMM dd yyyy :Thursday, August 17 2000

    * ddd, MMM d "'"yy :Thu, Aug 17 '00

    * dddd, MMMM dd :Thursday, August 17

    * M/yy :8/00

    * dd-MM-yy :17-08-00

    */

    }

}