using System.Numerics;

public class Program
{
    public static void Main()
    {

        //int num = int.Parse(Console.ReadLine() ?? string.Empty);
        //string[] str = (Console.ReadLine() ?? string.Empty).Trim().Split(' ');
        string str = Console.ReadLine() ?? string.Empty;

        if(str == "A" ||str == "C" ||str == "D" ||str == "F" ||str == "G")
        {
            Console.WriteLine("{0}" + "#");
        }
        else if(str== "E")
        {
            Console.WriteLine("F");
        }
        else
        {
            Console.WriteLine("C");
        }


    }
}