import java.util.Scanner;

public 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 a='A';
		char[] c = s.toCharArray();
		for(int i=0;i<c.length;i++) {
			if(c[i]+n>=a+26) {
				c[i]=(char)(c[i]+n-26);
			}else {
				c[i]+=n;
			}
			System.out.print(c[i]);
		}
		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