import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
			String srt=sc.nextLine();
			String srt2="AAA";
			String srt3="BBB";
			if(srt.equals(srt2)||srt.equals(srt3)){
				System.out.println("No");
			}
			else{
				System.out.println("Yes");
			}
		}
	}

/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