import java.util.Scanner;

class Main {

	public static void main(String[] args) {

		Scanner scan = new Scanner(System.in);
		int n = scan.nextInt();
		String s = scan.next();
		scan.close();

		char[] c = s.toCharArray();
		for (int i = 0; i < s.length(); i++) {
			int c1 = c[i] + n;
			if (c1 > 90)
				c1 = c1 - 26;
			System.out.print((char) c1);

		}
	}
}
/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