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 C (GCC 9.2.1) (judge verdict: Accepted)

#include <stdio.h>
int main (){
	char S[100];
	scanf("%s",S);
	if (S[1]=='B'){
		S[1]='R';
		printf("%s", S);
	}
	else if (S[1]=='R') {
		S[1]='B';
		printf("%s", S);
	}
	
return 0;
}