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 sys, math
a, b = map (int, input ().split())
ans = 0
target = math.gcd (a, b)
if target == a and target == b :
	print (0)
	sys.exit()
aRatio = a / target 
bRatio = b / target 
if aRatio % 5 == 0 :
	ans += aRatio / 5
elif aRatio % 3 == 0 :
	ans += aRatio / 3
elif aRatio % 2 == 0 :
	ans += aRatio / 2
else :
	print (-1)
	sys.exit ()
if bRatio % 5 == 0 :
	ans += bRatio / 5
elif bRatio % 3 == 0 :
	ans += bRatio / 3
elif bRatio % 2 == 0 :
	ans += bRatio / 2
else :
	print (-1)
	sys.exit ()
print (int (ans))