import java.util.*;
class Main{
    public static void main(String[] args){
      	Scanner sc=new Scanner(System.in);
        String S=sc.next();
      	boolean f= (S.charAt(0)==S.charAt(1))&&(S.charAt(2)==S.charAt(1));
      	System.out.println(f?"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