import java.util.Scanner;
public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        boolean not = true;
        if (a.charAt(1) == a.charAt(0)) {
            if (a.charAt(2) == a.charAt(1)) {
                System.out.println("No");
            }
            else {
                System.out.println("Yes");
            }
        }
        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