import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
      String s1 = "ABC";
      String s2 = "ARC";
      boolean t1 = true;
      boolean t2 = true;
		for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      }
      	for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      }
       if(t1==true){
          System.out.println(s2);
           }
       if(t2==true){
          System.out.println(s1); 
          }
	}
} 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 s1 = "ABC";
      String s2 = "ARC";
      boolean t1 = true;
      boolean t2 = true;
		for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      }
      	for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      }
       if(t1==true){
          System.out.println(s2);
           }
       if(t2==true){
          System.out.println(s1); 
          }
	}
} Main public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
      String s1 = "ABC";
      String s2 = "ARC";
      boolean t1 = true;
      boolean t2 = true;
		for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      }
      	for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      }
       if(t1==true){
          System.out.println(s2);
           }
       if(t2==true){
          System.out.println(s1); 
          }
	} main {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
      String s1 = "ABC";
      String s2 = "ARC";
      boolean t1 = true;
      boolean t2 = true;
		for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      }
      	for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      }
       if(t1==true){
          System.out.println(s2);
           }
       if(t2==true){
          System.out.println(s1); 
          }
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc String s1 = "ABC"; s1 "ABC" String s2 = "ARC"; s2 "ARC" boolean t1 = true; t1 true boolean t2 = true; t2 true for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      } int i = 0; int i = 0; i 0 i<s.length() i s.length() s.length s i++ i++ i {
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      } {
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      } if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         } s.charAt(i)!=s1.charAt(i) s.charAt(i) s.charAt s i s1.charAt(i) s1.charAt s1 i {
            t1 = false;
            break;
         } t1 = false t1 false break; for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      } int i = 0; int i = 0; i 0 i<s.length() i s.length() s.length s i++ i++ i {
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      } {
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      } if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         } s.charAt(i)!=s2.charAt(i) s.charAt(i) s.charAt s i s2.charAt(i) s2.charAt s2 i {
            t2 = false;
            break;
         } t2 = false t2 false break; if(t1==true){
          System.out.println(s2);
           } t1==true t1 true {
          System.out.println(s2);
           } System.out.println(s2) System.out.println System.out System System.out s2 if(t2==true){
          System.out.println(s1); 
          } t2==true t2 true {
          System.out.println(s1); 
          } System.out.println(s1) System.out.println System.out System System.out s1 String[] args args public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
      String s1 = "ABC";
      String s2 = "ARC";
      boolean t1 = true;
      boolean t2 = true;
		for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      }
      	for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      }
       if(t1==true){
          System.out.println(s2);
           }
       if(t2==true){
          System.out.println(s1); 
          }
	}
} public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
      String s1 = "ABC";
      String s2 = "ARC";
      boolean t1 = true;
      boolean t2 = true;
		for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      }
      	for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      }
       if(t1==true){
          System.out.println(s2);
           }
       if(t2==true){
          System.out.println(s1); 
          }
	}
} Main
import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
      String s1 = "ABC";
      String s2 = "ARC";
      boolean t1 = true;
      boolean t2 = true;
		for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s1.charAt(i)){
            t1 = false;
            break;
         }
      }
      	for(int i = 0;i<s.length();i++){
         if(s.charAt(i)!=s2.charAt(i)){
            t2 = false;
            break;
         }
      }
       if(t1==true){
          System.out.println(s2);
           }
       if(t2==true){
          System.out.println(s1); 
          }
	}
}
