class Program
 {
     static void Main(string[] args)
     {
         string soundName = Console.ReadLine();
         if(soundName != "E" && soundName != "B")
         {
             Console.WriteLine(soundName + "#");
         }else if(soundName == "E")
         {
             Console.WriteLine("F");
         }
         else
         {
             Console.WriteLine("C");
         }
     }
 }