
import java.util.Scanner;

/**
 * @author yoshizaki
 *
 */
public class Main {
    public static void main(String[] args) {
        Scanner scanner= new Scanner(System.in);
        String station = scanner.nextLine();
        if (station.indexOf("A")>=0 && station.indexOf("B")>=0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
}

/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