import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        OutputStream outputStream = System.out;
        PrintWriter out = new PrintWriter(outputStream);
        FastReader in = new FastReader();
        test a=new test();
        a.solve(in,out);
        out.close();
    }
}
class test{
    public void solve(FastReader in, PrintWriter out){
       String s =in.next();
       if(s.equals("ABC")){
           out.println("ARC");
       }else{
           out.println("ABC");
       }
    }

}

class FastReader{
    BufferedReader br;
    StringTokenizer st;

    public FastReader(){
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next(){
        while(st==null || !st.hasMoreElements()){
            try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt(){
        return Integer.parseInt(next());
    }

    Long nextLong(){
        return Long.parseLong(next());
    }

    double nextDouble(){
        return Double.parseDouble(next());
    }
    String nextLine(){
        String str="";
        try{
            str=br.readLine();
        }
        catch(IOException e){
            e.printStackTrace();
        }
        return str;
    }
}
 import java.io.*; io.* java import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws IOException {
        OutputStream outputStream = System.out;
        PrintWriter out = new PrintWriter(outputStream);
        FastReader in = new FastReader();
        test a=new test();
        a.solve(in,out);
        out.close();
    }
} Main public static void main(String[] args) throws IOException {
        OutputStream outputStream = System.out;
        PrintWriter out = new PrintWriter(outputStream);
        FastReader in = new FastReader();
        test a=new test();
        a.solve(in,out);
        out.close();
    } main {
        OutputStream outputStream = System.out;
        PrintWriter out = new PrintWriter(outputStream);
        FastReader in = new FastReader();
        test a=new test();
        a.solve(in,out);
        out.close();
    } OutputStream outputStream = System.out; outputStream System.out System System.out PrintWriter out = new PrintWriter(outputStream); out new PrintWriter(outputStream) FastReader in = new FastReader(); in new FastReader() test a=new test(); a new test() a.solve(in,out) a.solve a in out out.close() out.close out String[] args args class test{
    public void solve(FastReader in, PrintWriter out){
       String s =in.next();
       if(s.equals("ABC")){
           out.println("ARC");
       }else{
           out.println("ABC");
       }
    }

} test public void solve(FastReader in, PrintWriter out){
       String s =in.next();
       if(s.equals("ABC")){
           out.println("ARC");
       }else{
           out.println("ABC");
       }
    } solve {
       String s =in.next();
       if(s.equals("ABC")){
           out.println("ARC");
       }else{
           out.println("ABC");
       }
    } String s =in.next(); s in.next() in.next in if(s.equals("ABC")){
           out.println("ARC");
       }else{
           out.println("ABC");
       } s.equals("ABC") s.equals s "ABC" {
           out.println("ARC");
       } out.println("ARC") out.println out "ARC" {
           out.println("ABC");
       } out.println("ABC") out.println out "ABC" FastReader in in PrintWriter out out class FastReader{
    BufferedReader br;
    StringTokenizer st;

    public FastReader(){
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next(){
        while(st==null || !st.hasMoreElements()){
            try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt(){
        return Integer.parseInt(next());
    }

    Long nextLong(){
        return Long.parseLong(next());
    }

    double nextDouble(){
        return Double.parseDouble(next());
    }
    String nextLine(){
        String str="";
        try{
            str=br.readLine();
        }
        catch(IOException e){
            e.printStackTrace();
        }
        return str;
    }
} FastReader BufferedReader br; br StringTokenizer st; st public FastReader(){
        br = new BufferedReader(new InputStreamReader(System.in));
    } FastReader {
        br = new BufferedReader(new InputStreamReader(System.in));
    } br = new BufferedReader(new InputStreamReader(System.in)) br new BufferedReader(new InputStreamReader(System.in)) String next(){
        while(st==null || !st.hasMoreElements()){
            try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            }
        }
        return st.nextToken();
    } next {
        while(st==null || !st.hasMoreElements()){
            try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            }
        }
        return st.nextToken();
    } while(st==null || !st.hasMoreElements()){
            try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            }
        } st==null || !st.hasMoreElements() st==null st null !st.hasMoreElements() st.hasMoreElements() st.hasMoreElements st {
            try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            }
        } try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            } catch(IOException e){
                e.printStackTrace();
            } IOException e {
                e.printStackTrace();
            } e.printStackTrace() e.printStackTrace e {
                st=new StringTokenizer(br.readLine());
            } st=new StringTokenizer(br.readLine()) st new StringTokenizer(br.readLine()) return st.nextToken(); st.nextToken() st.nextToken st int nextInt(){
        return Integer.parseInt(next());
    } nextInt {
        return Integer.parseInt(next());
    } return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next Long nextLong(){
        return Long.parseLong(next());
    } nextLong {
        return Long.parseLong(next());
    } return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next double nextDouble(){
        return Double.parseDouble(next());
    } nextDouble {
        return Double.parseDouble(next());
    } return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next String nextLine(){
        String str="";
        try{
            str=br.readLine();
        }
        catch(IOException e){
            e.printStackTrace();
        }
        return str;
    } nextLine {
        String str="";
        try{
            str=br.readLine();
        }
        catch(IOException e){
            e.printStackTrace();
        }
        return str;
    } String str=""; str "" try{
            str=br.readLine();
        }
        catch(IOException e){
            e.printStackTrace();
        } catch(IOException e){
            e.printStackTrace();
        } IOException e {
            e.printStackTrace();
        } e.printStackTrace() e.printStackTrace e {
            str=br.readLine();
        } str=br.readLine() str br.readLine() br.readLine br return str; str public class Main {
    public static void main(String[] args) throws IOException {
        OutputStream outputStream = System.out;
        PrintWriter out = new PrintWriter(outputStream);
        FastReader in = new FastReader();
        test a=new test();
        a.solve(in,out);
        out.close();
    }
} public class Main {
    public static void main(String[] args) throws IOException {
        OutputStream outputStream = System.out;
        PrintWriter out = new PrintWriter(outputStream);
        FastReader in = new FastReader();
        test a=new test();
        a.solve(in,out);
        out.close();
    }
} Main
import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        OutputStream outputStream = System.out;
        PrintWriter out = new PrintWriter(outputStream);
        FastReader in = new FastReader();
        test a=new test();
        a.solve(in,out);
        out.close();
    }
}
class test{
    public void solve(FastReader in, PrintWriter out){
       String s =in.next();
       if(s.equals("ABC")){
           out.println("ARC");
       }else{
           out.println("ABC");
       }
    }

}

class FastReader{
    BufferedReader br;
    StringTokenizer st;

    public FastReader(){
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next(){
        while(st==null || !st.hasMoreElements()){
            try{
                st=new StringTokenizer(br.readLine());
            }
            catch(IOException e){
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt(){
        return Integer.parseInt(next());
    }

    Long nextLong(){
        return Long.parseLong(next());
    }

    double nextDouble(){
        return Double.parseDouble(next());
    }
    String nextLine(){
        String str="";
        try{
            str=br.readLine();
        }
        catch(IOException e){
            e.printStackTrace();
        }
        return str;
    }
}

