import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		String s = sc.next();
		char[] ch = new char[s.length()];
		for (int i = 0; i < ch.length; i++) {
			ch[i] = s.charAt(i);
		}
		for (int i = 0; i < ch.length; i++) {
			int j = ch[i];

			if (j + n > 90) {
				j = j - 26 + n;
			} else {
				j = ch[i] + n;
			}
			System.out.print((char) (j));
		}
		sc.close();
	}
}

/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