public class Main {
  public static void main(String[] args) {
    String s = new java.util.Scanner(System.in).nextLine();
    if(s.equals("ABC")) {
      System.out.println("ARC");
    }else{
      System.out.println("ABC");
    }
  }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz