import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String n = sc.next();
      	//System.out.println(n);
      	if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        }
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String n = sc.next();
      	//System.out.println(n);
      	if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        }
    }
} Main public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String n = sc.next();
      	//System.out.println(n);
      	if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        }
    } main {
        Scanner sc = new Scanner(System.in);
        String n = sc.next();
      	//System.out.println(n);
      	if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        }
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String n = sc.next(); n sc.next() sc.next sc if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        } n.equals("AAA") || n.equals("BBB") n.equals("AAA") n.equals n "AAA" n.equals("BBB") n.equals n "BBB" {
          System.out.print("No");
        } System.out.print("No") System.out.print System.out System System.out "No" {
          System.out.print("Yes");
        } System.out.print("Yes") System.out.print System.out System System.out "Yes" String[] args args public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String n = sc.next();
      	//System.out.println(n);
      	if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        }
    }
} public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String n = sc.next();
      	//System.out.println(n);
      	if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        }
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String n = sc.next();
      	//System.out.println(n);
      	if(n.equals("AAA") || n.equals("BBB")){
          System.out.print("No");
        }else{
          System.out.print("Yes");
        }
    }
}