import java.io.*;
import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
//        sc.useDelimiter("\n");
//        DecimalFormat df = new DecimalFormat("0.00000000");
        
        String s = sc.next();
        pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes");
        
        pw.flush();
    }
} import java.io.*; io.* java import java.util.*; util.* java public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
//        sc.useDelimiter("\n");
//        DecimalFormat df = new DecimalFormat("0.00000000");
        
        String s = sc.next();
        pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes");
        
        pw.flush();
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
//        sc.useDelimiter("\n");
//        DecimalFormat df = new DecimalFormat("0.00000000");
        
        String s = sc.next();
        pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes");
        
        pw.flush();
    } main {
        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
//        sc.useDelimiter("\n");
//        DecimalFormat df = new DecimalFormat("0.00000000");
        
        String s = sc.next();
        pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes");
        
        pw.flush();
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) PrintWriter pw = new PrintWriter(System.out); pw new PrintWriter(System.out) String s = sc.next(); s sc.next() sc.next sc pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes") pw.println pw s.equals("AAA") || s.equals("BBB") ? "No" : "Yes" s.equals("AAA") || s.equals("BBB") s.equals("AAA") s.equals s "AAA" s.equals("BBB") s.equals s "BBB" "No" "Yes" pw.flush() pw.flush pw String[] args args public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
//        sc.useDelimiter("\n");
//        DecimalFormat df = new DecimalFormat("0.00000000");
        
        String s = sc.next();
        pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes");
        
        pw.flush();
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
//        sc.useDelimiter("\n");
//        DecimalFormat df = new DecimalFormat("0.00000000");
        
        String s = sc.next();
        pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes");
        
        pw.flush();
    }
} Main
import java.io.*;
import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
//        sc.useDelimiter("\n");
//        DecimalFormat df = new DecimalFormat("0.00000000");
        
        String s = sc.next();
        pw.println(s.equals("AAA") || s.equals("BBB") ? "No" : "Yes");
        
        pw.flush();
    }
}