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 JavaScript (Node.js 12.16.1) (judge verdict: Accepted)

'use strict';
function main(input) {
    var arg = input.trim().split('\n')[0]
    if (arg === 'ABC') {
      
  	console.log('ARC')
    } else{
      console.log('ABC')
    }
}
 
main(require('fs').readFileSync('/dev/stdin', 'utf8'));