import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
      int a = sc.nextInt();
		// 文字列の入力
		String s = sc.next();
      byte[] asciiCodes;
        asciiCodes = s.getBytes();
      int b = 'Z';
      for (int i = 0; i < asciiCodes.length; i++) {
      	asciiCodes[i] += a;
        if (asciiCodes[i] > b) {
          asciiCodes[i] -= 26;
        }
      }
      String resultString = new String(asciiCodes);
      // 出力
		System.out.println(resultString);
      
	}
}
/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