import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        // B - ROT N

        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();

        String s = sc.next();

        byte[] bs = s.getBytes();
        byte[] bp = new byte[bs.length];

        for (int i = 0; i < bs.length; i++) {
            bp[i] = (byte) (bs[i] + (byte)n);
            if (bp[i] > 90) bp[i] -= 26;
        }

//        System.out.println(Arrays.toString(bs));
//        System.out.println(Arrays.toString(bp));
        for (byte b : bp) {
            System.out.print((char)b);
        }
        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