import java.util.*;
public class Main {

  public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      String s = sc.next();
      StringBuilder sb = new StringBuilder();
      for(int i = 0; i < s.length(); i++) {
        int charNum = s.charAt(i) - 'A';
        charNum = (charNum + n) % 26 + 'A';
        sb.append((char)charNum);
      }
      System.out.println(sb.toString());
  }
}
/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