import java.util.*;

class Main {
	Scanner sc;
	
	void calc() {
		sc = new Scanner(System.in);
		int N = sc.nextInt();
		String s = sc.next();
		
		StringBuilder ans = new StringBuilder();
		for (int i = 0; i < s.length(); i++)
			ans.append( (char) ((s.charAt(i)-'A'+N)%26+'A') );
		System.out.println(ans.toString());
	}

	public static void main(String[] args) {
		new Main().calc();
	}
}
/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