
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        char[] s = in.next().toCharArray();
        boolean A = false;
        boolean B = false;
        for(int i = 0; i < s.length; i++) {
            if(s[i] == 'A') A = true;
            if(s[i] == 'B') B = true;
        }
        if(A && B)
            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