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 Kotlin (1.3.71) (judge verdict: Accepted)

fun main() {
    println(if (next() == "ABC") "ARC" else "ABC")
}

val sc = java.util.Scanner(System.`in`)
fun next() = sc.next()!!
fun nextInt() = sc.nextInt()
fun next2Int() = Pair(nextInt(), nextInt())
fun next3Int() = Triple(nextInt(), nextInt(), nextInt())
fun nextIntArray(size: Int) = IntArray(size) { nextInt() }
fun nextLong() = sc.nextLong()
fun nextLine() = sc.nextLine()!!
fun nextList() = nextLine().split(" ")
fun printYesNo(isYes: Boolean) = println(if (isYes) "Yes" else "No")
fun printString(action: StringBuilder.() -> Unit) = println(buildString(action))