import java.util.*;

public class Main {
  static final String ascii = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int index = sc.nextInt();
    String str = sc.next();
    
    if (index == 0){
      System.out.println(str);  
    }else {
    
      String replaced = "";
      for (int i = 0 ; i < str.length() ; i++){
        char c = str.charAt(i);
        int si = ascii.indexOf(String.valueOf(c));
        int ri = si + index;
        if(ri >= ascii.length()){
          ri = ri - ascii.length();
        }
        replaced = replaced + String.valueOf(ascii.charAt(ri));
      }
      System.out.println(replaced);
    }
  }
}
/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