Problem:
Score : 100 points

Problem Statement

AtCoder Inc. holds a contest every Saturday.

There are two types of contests called ABC and ARC, and just one of them is held at a time.

The company holds these two types of contests alternately: an ARC follows an ABC and vice versa.

Given a string S representing the type of the contest held last week, print the string representing the type of the contest held this week.

Constraints

S is ABC or ARC.

Input

Input is given from Standard Input in the following format:

S

Output

Print the string representing the type of the contest held this week.

Sample Input 1

ABC

Sample Output 1

ARC

They held an ABC last week, so they will hold an ARC this week.

Solution in Java (OpenJDK 11.0.6) (judge verdict: Runtime Error)

import java.util.Scanner;
public class Main {
	public static void main(String args[]) {
	Scanner scan=new Scanner(System.in);
	int N=scan.nextInt();
	int K=scan.nextInt();
	int A[]=new int[N];
	for(int i=0;i<N;i++) {
		A[i]=0;
	}
	for(int i=0;i<K;i++) {
	int d=scan.nextInt();
		for(int j=0;j<d;j++) {
			int m=scan.nextInt();
			A[m-1]=1;
		}
	}
	for(int i =0;i<N;i++) {
		if(A[i]==0) {
			System.out.println(i+1);
		}
		else {}
	}
	}
}