import java.util.Scanner;

// B - ROT N
// https://atcoder.jp/contests/abc146/tasks/abc146_b
public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int N = Integer.parseInt(scanner.next());
        char[] S = scanner.next().toCharArray();

        scanner.close();

        for (char c : S) {
            int tmp = c + N;
            if (tmp <= 90) {
                System.out.print((char) tmp);
            } else {
                System.out.print((char) (tmp % 90 + 64));
            }
        }
        System.out.println();
    }
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz