import java.util.*;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s=sc.next();
        if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        }
        System.out.println("No");
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s=sc.next();
        if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        }
        System.out.println("No");
    }
} Main public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s=sc.next();
        if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        }
        System.out.println("No");
    } main {
        Scanner sc = new Scanner(System.in);
        String s=sc.next();
        if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        }
        System.out.println("No");
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s=sc.next(); s sc.next() sc.next sc if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        } !s.equals("AAA")&&!s.equals("BBB") !s.equals("AAA") s.equals("AAA") s.equals s "AAA" !s.equals("BBB") s.equals("BBB") s.equals s "BBB" {
            System.out.println("Yes");
            return;
        } System.out.println("Yes") System.out.println System.out System System.out "Yes" return; System.out.println("No") System.out.println System.out System System.out "No" String[] args args public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s=sc.next();
        if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        }
        System.out.println("No");
    }
} public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s=sc.next();
        if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        }
        System.out.println("No");
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String s=sc.next();
        if(!s.equals("AAA")&&!s.equals("BBB")){
            System.out.println("Yes");
            return;
        }
        System.out.println("No");
    }
}