let ic c = int_of_char c - int_of_char '0'

let () =
  let n = Scanf.sscanf (input_line stdin) "%d" (fun a -> a) in
  let s = Scanf.sscanf (input_line stdin) "%s" (fun a -> a) in
  let ans = String.map (fun c ->
                let c' = ((int_of_char c - int_of_char 'A' + n) mod 26) + int_of_char 'A'
                in char_of_int c'
              ) s in
  print_string ans;
  print_newline ()
