import java.util.*;
public class Main{
  public static void main(String[] args){
    Scanner sc=new Scanner(System.in);
    String M =sc.next();
    if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{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 M =sc.next();
    if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");}
  }
} Main public static void main(String[] args){
    Scanner sc=new Scanner(System.in);
    String M =sc.next();
    if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");}
  } main {
    Scanner sc=new Scanner(System.in);
    String M =sc.next();
    if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");}
  } Scanner sc=new Scanner(System.in); sc new Scanner(System.in) String M =sc.next(); M sc.next() sc.next sc if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");} M.contains("AB") M.contains M "AB" {System.out.println("Yes");} System.out.println("Yes") System.out.println System.out System System.out "Yes" if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");} M.contains("BA") M.contains M "BA" {System.out.println("Yes");} System.out.println("Yes") System.out.println System.out System System.out "Yes" {System.out.println("No");} 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 M =sc.next();
    if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");}
  }
} public class Main{
  public static void main(String[] args){
    Scanner sc=new Scanner(System.in);
    String M =sc.next();
    if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");}
  }
} Main
import java.util.*;
public class Main{
  public static void main(String[] args){
    Scanner sc=new Scanner(System.in);
    String M =sc.next();
    if(M.contains("AB")){System.out.println("Yes");}
    else if(M.contains("BA")){System.out.println("Yes");}
            else{System.out.println("No");}
  }
}
