
import java.util.*;

public class Main {
	static public void main(String args[]){
		Scanner sc=new Scanner(System.in);
		 
		 String str=sc.next();
		 
		 if((str.charAt(0))==(str.charAt(1))&&
		 (str.charAt(2))==(str.charAt(1))&&
		 (str.charAt(0))==(str.charAt(2))){
		 	System.out.print("No");
		 }
		 else{
		 	System.out.print("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