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