import java.util.*;
public class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		String ans = " ";
		if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		}
		System.out.println(ans);
	}
} import java.util.*; util.* java public class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		String ans = " ";
		if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		}
		System.out.println(ans);
	}
} Main public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		String ans = " ";
		if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		}
		System.out.println(ans);
	} main {
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		String ans = " ";
		if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		}
		System.out.println(ans);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String S = sc.next(); S sc.next() sc.next sc String ans = " "; ans " " if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		} S.equals("ABC") S.equals S "ABC" {
			ans = "ARC";
		} ans = "ARC" ans "ARC" {
			ans = "ABC";
		} ans = "ABC" ans "ABC" System.out.println(ans) System.out.println System.out System System.out ans String args[] args public class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		String ans = " ";
		if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		}
		System.out.println(ans);
	}
} public class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		String ans = " ";
		if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		}
		System.out.println(ans);
	}
} Main
import java.util.*;
public class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		String ans = " ";
		if(S.equals("ABC")){
			ans = "ARC";
		}else{
			ans = "ABC";
		}
		System.out.println(ans);
	}
}