using System;

public class Program

{

    public static void Main()

    {

        var reportDate = DateTime.Now;

        var a = "{reportDate:yyMMdd}";

        var b = a.Replace("{reportDate:yyMMdd}",reportDate.ToString("yyMMdd"))

            .Replace("{reportDate:ddMMyy}",reportDate.ToString("ddMMyy"));

        Console.WriteLine(b);

    }

}