import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		}
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		}
		
	}
} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		}
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		}
		
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		}
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		}
		
	} main {
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		}
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		}
		
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String S = sc.next(); S sc.next() sc.next sc if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		} S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3) S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3) S.charAt(0) == S.charAt(1) S.charAt(0) S.charAt S 0 S.charAt(1) S.charAt S 1 S.charAt(1) == S.charAt(2) S.charAt(1) S.charAt S 1 S.charAt(2) S.charAt S 2 S.charAt(2) == S.charAt(3) S.charAt(2) S.charAt S 2 S.charAt(3) S.charAt S 3 {
			System.out.println("No");
			return;
		} System.out.println("No") System.out.println System.out System System.out "No" return; if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		} S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3) S.charAt(0) == S.charAt(1) S.charAt(0) S.charAt S 0 S.charAt(1) S.charAt S 1 S.charAt(2) == S.charAt(3) S.charAt(2) S.charAt S 2 S.charAt(3) S.charAt S 3 {
			System.out.println("Yes");
		} System.out.println("Yes") System.out.println System.out System System.out "Yes" if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		} S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3) S.charAt(0) == S.charAt(2) S.charAt(0) S.charAt S 0 S.charAt(2) S.charAt S 2 S.charAt(1) == S.charAt(3) S.charAt(1) S.charAt S 1 S.charAt(3) S.charAt S 3 {
			System.out.println("Yes");
		} System.out.println("Yes") System.out.println System.out System System.out "Yes" if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		} S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2) S.charAt(0) == S.charAt(3) S.charAt(0) S.charAt S 0 S.charAt(3) S.charAt S 3 S.charAt(1) == S.charAt(2) S.charAt(1) S.charAt S 1 S.charAt(2) S.charAt S 2 {
			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 S = sc.next();
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		}
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			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 S = sc.next();
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		}
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		}
		
	}
} Main
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(1) == S.charAt(2) && S.charAt(2) == S.charAt(3)) {
			System.out.println("No");
			return;
		}
		
		if(S.charAt(0) == S.charAt(1) && S.charAt(2) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(2) && S.charAt(1) == S.charAt(3)) {
			System.out.println("Yes");
		} else if(S.charAt(0) == S.charAt(3) && S.charAt(1) == S.charAt(2)) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		}
		
	}
}
