let () =
  let s = read_line () in
  print_endline @@
  match
    List.find (fun i -> s.[i] = 'C') @@
      Array.to_list @@
      Array.init (String.length s) @@
      fun i -> i
  with
  | exception Not_found -> "No"
  | i ->
      if 
        List.exists (( = ) 'F') @@
          Array.to_list @@
          Array.init (String.length s - i - 1) @@
          fun j -> s.[i + j + 1]
      then "Yes"
      else "No"
