Data Types C#

using System;
class MainClass{
   public static void Main(){  
        DayOfWeek thisDay = DayOfWeek.Monday;
        string[] formatStrings = {"G", "F", "D", "X"};
        
        foreach (string formatString in formatStrings)
           Console.WriteLine(thisDay.ToString(formatString));
   }
}
/*
Monday
Monday
1
00000001
*/