def main():
	a,b,c=input().split()
	if a=='?':
		if b=='2':
			print(4)
		else:
			print(1)
	elif b=='?':
		print(1)
	else:
		if b=='2':
			print(4)
		else:
			print(1)

if __name__=="__main__":
	main()