import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();

        String alphabets = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

        String result = "";

        for (int i = 0; i < s.length(); i++) {
            int idx1 = alphabets.indexOf(s.charAt(i));
            int key = i + 1;
            int idx2 = (idx1 - key) % alphabets.length();

            if (idx2 < 0) {
                idx2 += alphabets.length();
            }

            result += alphabets.charAt(idx2);
        }

        System.out.println(result);

        sc.close();
    }

}