Two little greedy bears have found two pieces of cheese in the forest of weight *a* and *b* grams, correspondingly. The bears are so greedy that they are ready to fight for the larger piece. That's where the fox comes in and starts the dialog: "Little bears, wait a little, I want to make your pieces equal" "Come off it fox, how are you going to do that?", the curious bears asked. "It's easy", said the fox. "If the mass of a certain piece is divisible by two, then I can eat exactly a half of the piece. If the mass of a certain piece is divisible by three, then I can eat exactly two-thirds, and if the mass is divisible by five, then I can eat four-fifths. I'll eat a little here and there and make the pieces equal". 

The little bears realize that the fox's proposal contains a catch. But at the same time they realize that they can not make the two pieces equal themselves. So they agreed to her proposal, but on one condition: the fox should make the pieces equal as quickly as possible. Find the minimum number of operations the fox needs to make pieces equal.
The first line contains two space-separated integers *a* and *b* (1 ≤ *a*, *b* ≤ 10<sup class="upper-index">9</sup>).
def compute_hcf(x, y):

# choose the smaller number
    if x > y:
        smaller = y
    else:
        smaller = x
    for i in range(1, smaller+1):
        if((x % i == 0) and (y % i == 0)):
            hcf = i 
    return hcf

a,b = map(int, input().split())

hcf = compute_hcf(a, b)

a = a/hcf
b = b/hcf
count = int(0)
# print(a,b,hcf)
while b>=2:
	# print(b)
	if b%2==0:
		count+=1
		b = b/2
	elif b%3==0:
		count+=1
		b = b/3
	elif b%5==0:
		count+=1
		b = b/5
	else:
		break


while a>=2:
	# print(a)
	if a%2==0:
		count+=1
		a = a/2
	elif a%3==0:
		count+=1
		a = a/3
	elif a%5==0:
		count+=1
		a = a/5
	else:
		break
	# print(a,b)
if(a!=b):
	print(-1)
else:
	print(count)

