import java.util.*;

public class Main {
    public static void main(String[] args){
        Scanner scn = new Scanner(System.in);
        int n = scn.nextInt();
        char[] a = scn.next().toCharArray();
        for(char tmp : a) {
            int num = 0;
            if((char)(tmp + n) > 'Z'){
                num = n - 26;
                System.out.print((char)(tmp + num));
            }else {
                System.out.print((char) (tmp + n));
            }
        }
    }
}
/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