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 Python (3.8.2) (judge verdict: Runtime Error)

X = int(input())

a = [int( i/2)*((-1)**i) for i in range(1, 1000)]
b = [int( i/2)*((-1)**i) for i in range(1, 1000)]

"""
* Aが正ならBは負または、Aより小さい正
* Aが負ならBは負
* X/(a+b)は、1以上の整数
"""

find = False
if X == 0:
  print(0)
else:  
  for a_ in a:
    for b_ in b:
      if a_ + b_ == 0:
        continue
      if a_ >= 0:
        if b_ >= 0 or b_ > a_:
          continue
      if a_ < 0:
        if b_ >= 0:
          continue
        
      if X%(a_+b_) != 0:
        continue
      
      if (a_**5) - (b_**5) == X:
        print(f"{a_} {b_}")
        find = True
        break
    if find:
      break