import java.util.*;

public class Main {

  static Scanner scan = new Scanner(System.in);

  public static void main(String[] args) {
    String t = scan.next();

    System.out.print(t.equals("ARC") ? "ABC" : "ARC");
  }
} import java.util.*; util.* java public class Main {

  static Scanner scan = new Scanner(System.in);

  public static void main(String[] args) {
    String t = scan.next();

    System.out.print(t.equals("ARC") ? "ABC" : "ARC");
  }
} Main static Scanner scan = new Scanner(System.in); scan new Scanner(System.in) public static void main(String[] args) {
    String t = scan.next();

    System.out.print(t.equals("ARC") ? "ABC" : "ARC");
  } main {
    String t = scan.next();

    System.out.print(t.equals("ARC") ? "ABC" : "ARC");
  } String t = scan.next(); t scan.next() scan.next scan System.out.print(t.equals("ARC") ? "ABC" : "ARC") System.out.print System.out System System.out t.equals("ARC") ? "ABC" : "ARC" t.equals("ARC") t.equals t "ARC" "ABC" "ARC" String[] args args public class Main {

  static Scanner scan = new Scanner(System.in);

  public static void main(String[] args) {
    String t = scan.next();

    System.out.print(t.equals("ARC") ? "ABC" : "ARC");
  }
} public class Main {

  static Scanner scan = new Scanner(System.in);

  public static void main(String[] args) {
    String t = scan.next();

    System.out.print(t.equals("ARC") ? "ABC" : "ARC");
  }
} Main
import java.util.*;

public class Main {

  static Scanner scan = new Scanner(System.in);

  public static void main(String[] args) {
    String t = scan.next();

    System.out.print(t.equals("ARC") ? "ABC" : "ARC");
  }
}