import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String s = scan.next();
        char[] c = s.toCharArray();
        int a = 1;
        for (int i = 0; i < c.length; i++) {
            int b = c[i] - 'A' - a;
            while (b < 0) {
                b += 26;
            }
            c[i] = (char)('A' + b);
            a++;
        }
        System.out.println(String.valueOf(c));
        scan.close();
    }
}