import java.util.Scanner;

public class Main {
    public static void main(String args[]) throws Exception{
        
      Scanner s = new Scanner(System.in);
        String input = s.nextLine();
      
      boolean isSame = String.valueOf(input.charAt(0)).equals(String.valueOf(input.charAt(1))) &&
        				String.valueOf(input.charAt(1)).equals(String.valueOf(input.charAt(2)));
   
    	System.out.println(isSame ? "No" : "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