import java.util.Scanner;

/**
 * yukicoder no.18
 * @author scache
 *
 */
public class Main {
	public static void main(String[] args) {
		Main p = new Main();
	}

	public Main() {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		solve(s);
	}

	public void solve(String s) {
		StringBuilder sb = new StringBuilder(s.length());
		for(int i=0;i<s.length();i++){
			sb.append((char)((26+(s.charAt(i)-'A'-(i+1)%26))%26+'A'));
		}
		System.out.println(sb.toString());
	}

}