import java.io.*;

import java.math.BigInteger;
import java.util.*;

import java.util.ArrayList;

import java.util.Scanner;


public class Main {

    static 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;
        }
    }

    static final int mod = 1000000007;

    public static int gcd(int a, int b)
    {
        if (a == 0)
            return b;
        return gcd(b % a, a);
    }


    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s=sc.nextLine();
        if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC");

    }
}






 import java.io.*; io.* java import java.math.BigInteger; BigInteger java.math import java.util.*; util.* java import java.util.ArrayList; ArrayList java.util import java.util.Scanner; Scanner java.util public class Main {

    static 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;
        }
    }

    static final int mod = 1000000007;

    public static int gcd(int a, int b)
    {
        if (a == 0)
            return b;
        return gcd(b % a, a);
    }


    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s=sc.nextLine();
        if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC");

    }
} Main static final int mod = 1000000007; mod 1000000007 public static int gcd(int a, int b)
    {
        if (a == 0)
            return b;
        return gcd(b % a, a);
    } gcd {
        if (a == 0)
            return b;
        return gcd(b % a, a);
    } if (a == 0)
            return b; a == 0 a 0 return b; b return gcd(b % a, a); gcd(b % a, a) gcd b % a b a a int a a int b b public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s=sc.nextLine();
        if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC");

    } main {
        Scanner sc = new Scanner(System.in);
        String s=sc.nextLine();
        if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC");

    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s=sc.nextLine(); s sc.nextLine() sc.nextLine sc if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC"); s.charAt(1)=='B' s.charAt(1) s.charAt s 1 '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[] args args static 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 {

    static 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;
        }
    }

    static final int mod = 1000000007;

    public static int gcd(int a, int b)
    {
        if (a == 0)
            return b;
        return gcd(b % a, a);
    }


    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s=sc.nextLine();
        if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC");

    }
} public class Main {

    static 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;
        }
    }

    static final int mod = 1000000007;

    public static int gcd(int a, int b)
    {
        if (a == 0)
            return b;
        return gcd(b % a, a);
    }


    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s=sc.nextLine();
        if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC");

    }
} Main
import java.io.*;

import java.math.BigInteger;
import java.util.*;

import java.util.ArrayList;

import java.util.Scanner;


public class Main {

    static 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;
        }
    }

    static final int mod = 1000000007;

    public static int gcd(int a, int b)
    {
        if (a == 0)
            return b;
        return gcd(b % a, a);
    }


    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s=sc.nextLine();
        if(s.charAt(1)=='B')
            System.out.println("ARC");
        else
            System.out.println("ABC");

    }
}







