// package app;
import java.util.*;

public class Main {
    public static void main(String[] args) {    
        Scanner sc = new Scanner(System.in);
        String str = sc.next();
        sc.close();
        
        if (str.contains("A") && str.contains("B")){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
        System.exit(0);
    }
}
/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