import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		sc.nextLine();
		String s = sc.nextLine();

		char[] str = s.toCharArray();



		for(int i=0; i<str.length;i++) {
			int num = str[i] + N;
			char c  = (char)(num);
			if( c > 'Z')
				c = (char)(c - 26);
			System.out.print(c);
		}


		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