import java.util.Scanner;

public class Main {

  public static void main(String[] args ){

    Scanner sc = new Scanner(System.in);

    String S = sc.next();
    boolean containsA = S.contains("A");
    boolean containsB = S.contains("B");

    System.out.println((containsA && containsB) ? "Yes" : "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