import java.util.Arrays;
import java.util.List;
import java.util.Scanner;

/**
 * B - ROT N
 */
public class Main {

    public static void main(String[] args) {

        Scanner sc = new Scanner( System.in );
        // 文字列の桁数
        int n = sc.nextInt();
        String s = sc.next();
        String result = "";

        List<String> alphabetsList = Arrays.asList( "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z" );

        for( int i = 0; i < s.length(); i++ ) {
//            System.out.println("charat : " + s.charAt( i ));
            int key = alphabetsList.indexOf( String.valueOf( s.charAt( i ) ) );
            if( key + n >= 26 ) {
                key -= 26;
            }
//            System.out.println("key : " + key );
            result += alphabetsList.get( key + n );
        }

        System.out.println( result );

        sc.close();
    }
}
/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