b1,b2,b3 = map(int,input().split())
flag = True
for d in range(-10**5,10**5+1):
	if (b2 - d) % b1 == 0:
		r = (b2 - d) // b1
		if b3 == b2 * r + d:
			flag = False
			print(b3 * r + d)
if flag:
	print(0)