import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		String string = sc.nextLine();

		if (string.equals("AAA") || string.equals("BBB")) {
			System.out.println("No");
		}else {
			System.out.println("Yes");
		}
	}
} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		String string = sc.nextLine();

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

		String string = sc.nextLine();

		if (string.equals("AAA") || string.equals("BBB")) {
			System.out.println("No");
		}else {
			System.out.println("Yes");
		}
	} main {
		Scanner sc = new Scanner(System.in);

		String string = sc.nextLine();

		if (string.equals("AAA") || string.equals("BBB")) {
			System.out.println("No");
		}else {
			System.out.println("Yes");
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String string = sc.nextLine(); string sc.nextLine() sc.nextLine sc if (string.equals("AAA") || string.equals("BBB")) {
			System.out.println("No");
		}else {
			System.out.println("Yes");
		} string.equals("AAA") || string.equals("BBB") string.equals("AAA") string.equals string "AAA" string.equals("BBB") string.equals string "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 sc = new Scanner(System.in);

		String string = sc.nextLine();

		if (string.equals("AAA") || string.equals("BBB")) {
			System.out.println("No");
		}else {
			System.out.println("Yes");
		}
	}
} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		String string = sc.nextLine();

		if (string.equals("AAA") || string.equals("BBB")) {
			System.out.println("No");
		}else {
			System.out.println("Yes");
		}
	}
} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		String string = sc.nextLine();

		if (string.equals("AAA") || string.equals("BBB")) {
			System.out.println("No");
		}else {
			System.out.println("Yes");
		}
	}
}