let rot13 c =
  if c >= 'a' && c < 'n' || c >= 'A' && c < 'N' then
    int_of_char(c) + 13
  else if c >= 'n' && c < '{' || c >= 'N' && c < '[' then
    int_of_char(c) - 13
  else int_of_char(c)

let _ =
  let input = read_line () in
    String.iter (fun c -> print_char (char_of_int (rot13 c))) input;
    print_newline ()