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 Scala (2.13.1) (judge verdict: Accepted)

import scala.io.StdIn.readLine
import scala.io.StdIn.readInt

object Main extends App {
  val s = readLine
  val ans = if(s == "ARC")"ABC" else "ARC"
  println(ans)                       // 結果を出力する
}