import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		String s = sc.next();
		
		if((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		}
		
	}
} 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((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		}
		
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		String s = sc.next();
		
		if((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		}
		
	} main {
		Scanner sc = new Scanner(System.in);
		
		String s = sc.next();
		
		if((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		}
		
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc if((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		} (char)s.charAt(1)=='B' (char)s.charAt(1) s.charAt s 1 'B' {
			System.out.println("ARC");
		} System.out.println("ARC") System.out.println System.out System System.out "ARC" {
			System.out.println("ABC");
		} System.out.println("ABC") System.out.println System.out System System.out "ABC" String[] args args public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		String s = sc.next();
		
		if((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		}
		
	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		String s = sc.next();
		
		if((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		}
		
	}
} 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((char)s.charAt(1)=='B') {
			System.out.println("ARC");
		}else {
			System.out.println("ABC");
		}
		
	}
}