using System;

public class Program

{

    public static void Main()

    {

        int index = 0;

      char[] chArray = new char[48];

      string strB = "OB>@QC{mo1e5_iv_`_6e5om_26_s4ov_`11i_81_o4s4o64}";

      Console.WriteLine("Put your flag: ");

      foreach (char c in strB)

      {

        int num = (int) c;

        if (char.IsLetter(c))

          num = num -2;

        if (char.IsLetterOrDigit(c))

          num = num +5;

        if (char.IsDigit(c))

          num = (int) c - 1 ;

​

          chArray[index] = Convert.ToChar(num);

        ++index;

          }

    Console.WriteLine(new string(chArray));

    Console.WriteLine(strB);

    }

}