
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.PriorityQueue;
import java.util.*;

public class Main {
	public static class pair implements Comparable<pair> {
		int id;
		int ans;

		pair(int x, int y) {

			id = x;
			ans = y;

		}

		public pair() {

		}

		public int compareTo(pair o) {
			// TODO Auto-generated method stub

			return this.id - o.id;
		}
	}

//	static int mod = (int) 998244353.;
	static ArrayList<Integer> gr[];
	static long ar[];
	static Scanner sc = new Scanner(System.in);
	static int pri[] = new int[(int) 1e6 + 5];
	static StringBuilder out = new StringBuilder();

	//static long dp[];

	public static void main(String[] args) throws IOException {
		int t =1;// sc.nextInt();
		
		while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		}

	}
} import java.io.DataInputStream; DataInputStream java.io import java.io.FileInputStream; FileInputStream java.io import java.io.IOException; IOException java.io import java.util.ArrayList; ArrayList java.util import java.util.Arrays; Arrays java.util import java.util.PriorityQueue; PriorityQueue java.util import java.util.*; util.* java public class Main {
	public static class pair implements Comparable<pair> {
		int id;
		int ans;

		pair(int x, int y) {

			id = x;
			ans = y;

		}

		public pair() {

		}

		public int compareTo(pair o) {
			// TODO Auto-generated method stub

			return this.id - o.id;
		}
	}

//	static int mod = (int) 998244353.;
	static ArrayList<Integer> gr[];
	static long ar[];
	static Scanner sc = new Scanner(System.in);
	static int pri[] = new int[(int) 1e6 + 5];
	static StringBuilder out = new StringBuilder();

	//static long dp[];

	public static void main(String[] args) throws IOException {
		int t =1;// sc.nextInt();
		
		while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		}

	}
} Main //	static int mod = (int) 998244353.;
	static ArrayList<Integer> gr[]; gr static long ar[]; ar static Scanner sc = new Scanner(System.in); sc new Scanner(System.in) static int pri[] = new int[(int) 1e6 + 5]; pri new int[(int) 1e6 + 5] (int) 1e6 + 5 (int) 1e6 5 static StringBuilder out = new StringBuilder(); out new StringBuilder() public static void main(String[] args) throws IOException {
		int t =1;// sc.nextInt();
		
		while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		}

	} main {
		int t =1;// sc.nextInt();
		
		while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		}

	} int t =1; t 1 while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		} t-- > 0 t-- t 0 {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		} String s1="ABC"; s1 "ABC" String s2="ARC"; s2 "ARC" String s=sc.next(); s sc.next() sc.next sc if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1); s.equals(s1) s.equals s s1 {
				System.out.println(s2);
			} System.out.println(s2) System.out.println System.out System System.out s2 System.out.println(s1) System.out.println System.out System System.out s1 String[] args args public static class pair implements Comparable<pair> {
		int id;
		int ans;

		pair(int x, int y) {

			id = x;
			ans = y;

		}

		public pair() {

		}

		public int compareTo(pair o) {
			// TODO Auto-generated method stub

			return this.id - o.id;
		}
	} pair int id; id int ans; ans pair(int x, int y) {

			id = x;
			ans = y;

		} pair {

			id = x;
			ans = y;

		} id = x id x ans = y ans y int x x int y y public pair() {

		} pair {

		} public int compareTo(pair o) {
			// TODO Auto-generated method stub

			return this.id - o.id;
		} compareTo {
			// TODO Auto-generated method stub

			return this.id - o.id;
		} return this.id - o.id; this.id - o.id this.id this this.id o.id o o.id pair o o Comparable public class Main {
	public static class pair implements Comparable<pair> {
		int id;
		int ans;

		pair(int x, int y) {

			id = x;
			ans = y;

		}

		public pair() {

		}

		public int compareTo(pair o) {
			// TODO Auto-generated method stub

			return this.id - o.id;
		}
	}

//	static int mod = (int) 998244353.;
	static ArrayList<Integer> gr[];
	static long ar[];
	static Scanner sc = new Scanner(System.in);
	static int pri[] = new int[(int) 1e6 + 5];
	static StringBuilder out = new StringBuilder();

	//static long dp[];

	public static void main(String[] args) throws IOException {
		int t =1;// sc.nextInt();
		
		while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		}

	}
} public class Main {
	public static class pair implements Comparable<pair> {
		int id;
		int ans;

		pair(int x, int y) {

			id = x;
			ans = y;

		}

		public pair() {

		}

		public int compareTo(pair o) {
			// TODO Auto-generated method stub

			return this.id - o.id;
		}
	}

//	static int mod = (int) 998244353.;
	static ArrayList<Integer> gr[];
	static long ar[];
	static Scanner sc = new Scanner(System.in);
	static int pri[] = new int[(int) 1e6 + 5];
	static StringBuilder out = new StringBuilder();

	//static long dp[];

	public static void main(String[] args) throws IOException {
		int t =1;// sc.nextInt();
		
		while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		}

	}
} Main

import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.PriorityQueue;
import java.util.*;

public class Main {
	public static class pair implements Comparable<pair> {
		int id;
		int ans;

		pair(int x, int y) {

			id = x;
			ans = y;

		}

		public pair() {

		}

		public int compareTo(pair o) {
			// TODO Auto-generated method stub

			return this.id - o.id;
		}
	}

//	static int mod = (int) 998244353.;
	static ArrayList<Integer> gr[];
	static long ar[];
	static Scanner sc = new Scanner(System.in);
	static int pri[] = new int[(int) 1e6 + 5];
	static StringBuilder out = new StringBuilder();

	//static long dp[];

	public static void main(String[] args) throws IOException {
		int t =1;// sc.nextInt();
		
		while (t-- > 0) {

			String s1="ABC";
			String s2="ARC";
			String s=sc.next();
			if(s.equals(s1)) {
				System.out.println(s2);
			}
			else System.out.println(s1);
		}

	}
}