a = int(input())
b = int(input())
c = int(input())
if a > b > c:
	print("ABC")
elif a > c > b:
	print("ACB")
elif b > a > c:
	print("BAC")
elif b > c > a:
	print("BCA")
elif c > a > b:
	print("CAB")
else:
	print("CBA")