let scan_int () = Scanf.scanf " %d" (fun x -> x)
let scan_string () = Scanf.scanf " %s" (fun x -> x)
let print_string s = Printf.printf "%s\n" s

let rot c n = Char.chr ((Char.code c - Char.code 'A' + n) mod 26 + Char.code 'A')

let convert s n =
  for i = 0 to String.length s - 1 do
    s.[i] <- rot s.[i] n
  done

let () =
  let n = scan_int() in
  let s = scan_string() in
  let () = convert s n in
  print_string s