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
inp = sys.stdin.readline().replace("\n","").split()
a = int(inp[0])
b = int(inp[1])
a_div = [0 for i in range(4)]
b_div = [0 for i in range(4)]
counter = 0
if a == b:
  print(0)
  sys.exit()
while a%2 == 0:
  a = a//2
  a_div[0] += 1
while a%3 == 0:
  a = a//3
  a_div[1] += 1
while a%5 == 0:
  a = a//5
  a_div[2] += 1
while b%2 == 0:
  b = b//2
  b_div[0] += 1
while b%3 == 0:
  b = b//3
  b_div[1] += 1
while b%5 == 0:
  b = b//5
  b_div[2] += 1
if a != b:
  print(-1)
  sys.exit()
for i in range(0, 3):
  counter += abs(a_div[i]-b_div[i])
print(counter)
 	   				  	  	        	 	  	