A - A?C

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.

ABC

ARC

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