import java.util.*;
 
public class Main{
  
 public static void main(String arg[])
 {
  Scanner sc=new Scanner(System.in);
   String s=sc.next();
   if(s.charAt(s.length()-2)=='B')System.out.println("ARC");
   else System.out.println("ABC");
 }
} import java.util.*; util.* java public class Main{
  
 public static void main(String arg[])
 {
  Scanner sc=new Scanner(System.in);
   String s=sc.next();
   if(s.charAt(s.length()-2)=='B')System.out.println("ARC");
   else System.out.println("ABC");
 }
} Main public static void main(String arg[])
 {
  Scanner sc=new Scanner(System.in);
   String s=sc.next();
   if(s.charAt(s.length()-2)=='B')System.out.println("ARC");
   else System.out.println("ABC");
 } main {
  Scanner sc=new Scanner(System.in);
   String s=sc.next();
   if(s.charAt(s.length()-2)=='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(s.charAt(s.length()-2)=='B')System.out.println("ARC");
   else System.out.println("ABC"); s.charAt(s.length()-2)=='B' s.charAt(s.length()-2) s.charAt s s.length()-2 s.length() s.length s 2 'B' System.out.println("ARC") System.out.println System.out System System.out "ARC" System.out.println("ABC") System.out.println System.out System System.out "ABC" String arg[] arg public class Main{
  
 public static void main(String arg[])
 {
  Scanner sc=new Scanner(System.in);
   String s=sc.next();
   if(s.charAt(s.length()-2)=='B')System.out.println("ARC");
   else System.out.println("ABC");
 }
} public class Main{
  
 public static void main(String arg[])
 {
  Scanner sc=new Scanner(System.in);
   String s=sc.next();
   if(s.charAt(s.length()-2)=='B')System.out.println("ARC");
   else System.out.println("ABC");
 }
} Main
import java.util.*;
 
public class Main{
  
 public static void main(String arg[])
 {
  Scanner sc=new Scanner(System.in);
   String s=sc.next();
   if(s.charAt(s.length()-2)=='B')System.out.println("ARC");
   else System.out.println("ABC");
 }
}
