import java.util.*;

public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
  	String s=sc.next();
    if(s.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("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.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("No");
    }
  }
} Main public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
  	String s=sc.next();
    if(s.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("No");
    }
  } main {
    Scanner sc = new Scanner(System.in);
  	String s=sc.next();
    if(s.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("No");
    }
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s=sc.next(); s sc.next() sc.next sc if(s.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("No");
    } s.indexOf("A")!=-1&&s.indexOf("B")!=-1 s.indexOf("A")!=-1 s.indexOf("A") s.indexOf s "A" -1 1 s.indexOf("B")!=-1 s.indexOf("B") s.indexOf s "B" -1 1 {
      System.out.print("Yes");
    } System.out.print("Yes") System.out.print System.out System System.out "Yes" {
      System.out.print("No");
    } System.out.print("No") System.out.print 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.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("No");
    }
  }
} public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
  	String s=sc.next();
    if(s.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("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.indexOf("A")!=-1&&s.indexOf("B")!=-1){
      System.out.print("Yes");
    }else{
      System.out.print("No");
    }
  }
}