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>).
import math
import sys
def sol(x):
	res=0
	while x%2==0:
		res+=1
		x=x//2
	while x%3==0:
		res+=1
		x=x//3
	while x%5==0:
		res+=1
		x=x//5
	if(x!=1):
		return -1
	else :
		return res
a,b=map(int,input().split())
d=math.gcd(a,b)
ans1=sol(a//d)
if(ans1==-1):
	print(-1)
	sys.exit()
ans2=sol(b//d)
if(ans2==-1):
	print(-1)
	sys.exit()
print(ans1+ans2)