import java.util.*;

public class Main {

	public static void main(String[] args) {

		Scanner keyboard = new Scanner(System.in);

		String S = keyboard.next();
		String ans = "ABC";
		if(S.equals("ABC")){
			ans = "ARC";
		}
		
		System.out.println(ans);
		keyboard.close();
	}
} import java.util.*; util.* java public class Main {

	public static void main(String[] args) {

		Scanner keyboard = new Scanner(System.in);

		String S = keyboard.next();
		String ans = "ABC";
		if(S.equals("ABC")){
			ans = "ARC";
		}
		
		System.out.println(ans);
		keyboard.close();
	}
} Main public static void main(String[] args) {

		Scanner keyboard = new Scanner(System.in);

		String S = keyboard.next();
		String ans = "ABC";
		if(S.equals("ABC")){
			ans = "ARC";
		}
		
		System.out.println(ans);
		keyboard.close();
	} main {

		Scanner keyboard = new Scanner(System.in);

		String S = keyboard.next();
		String ans = "ABC";
		if(S.equals("ABC")){
			ans = "ARC";
		}
		
		System.out.println(ans);
		keyboard.close();
	} Scanner keyboard = new Scanner(System.in); keyboard new Scanner(System.in) String S = keyboard.next(); S keyboard.next() keyboard.next keyboard String ans = "ABC"; ans "ABC" if(S.equals("ABC")){
			ans = "ARC";
		} S.equals("ABC") S.equals S "ABC" {
			ans = "ARC";
		} ans = "ARC" ans "ARC" System.out.println(ans) System.out.println System.out System System.out ans keyboard.close() keyboard.close keyboard String[] args args public class Main {

	public static void main(String[] args) {

		Scanner keyboard = new Scanner(System.in);

		String S = keyboard.next();
		String ans = "ABC";
		if(S.equals("ABC")){
			ans = "ARC";
		}
		
		System.out.println(ans);
		keyboard.close();
	}
} public class Main {

	public static void main(String[] args) {

		Scanner keyboard = new Scanner(System.in);

		String S = keyboard.next();
		String ans = "ABC";
		if(S.equals("ABC")){
			ans = "ARC";
		}
		
		System.out.println(ans);
		keyboard.close();
	}
} Main
import java.util.*;

public class Main {

	public static void main(String[] args) {

		Scanner keyboard = new Scanner(System.in);

		String S = keyboard.next();
		String ans = "ABC";
		if(S.equals("ABC")){
			ans = "ARC";
		}
		
		System.out.println(ans);
		keyboard.close();
	}
}
