let () =
    let main () =
        let n = int_of_string (read_line ()) in
        let s = read_line () in
        print_endline (String.map (fun c -> char_of_int(((int_of_char c - int_of_char 'A' + n) mod 26) + int_of_char 'A')) s)
    in
    main ()