

import java.util.Scanner;

public class Main {

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

		String a = sc.next();

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

} import java.util.Scanner; Scanner java.util public class Main {

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

		String a = sc.next();

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

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

		String a = sc.next();

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

		String a = sc.next();

		if (a.equals("AAA") | a.equals("BBB")) {
			System.out.print("No");
		} else {
			System.out.print("Yes");
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String a = sc.next(); a sc.next() sc.next sc if (a.equals("AAA") | a.equals("BBB")) {
			System.out.print("No");
		} else {
			System.out.print("Yes");
		} a.equals("AAA") | a.equals("BBB") a.equals("AAA") a.equals a "AAA" a.equals("BBB") a.equals a "BBB" {
			System.out.print("No");
		} System.out.print("No") System.out.print System.out System System.out "No" {
			System.out.print("Yes");
		} System.out.print("Yes") System.out.print 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 a = sc.next();

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

} public class Main {

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

		String a = sc.next();

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

} Main


import java.util.Scanner;

public class Main {

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

		String a = sc.next();

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

}
