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