s=eval(input())

print(('ARC' if s=='ABC' else 'ABC'))
print(("ABC" if eval(input())=="ARC" else "ARC"))
s = eval(input())
print(("ARC" if s == "ABC" else "ABC"))

print(("ABC" if eval(input()) == "ARC" else "ARC"))

-s = eval(input()) -print(("ARC" if s == "ABC" else "ABC")) +print(("ABC" if eval(input()) == "ARC" else "ARC"))