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>).
from fractions import Fraction

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

result = 0

while a != b:
    if a > b:
        minimum = b
        maximum = a
    else:
        minimum = a
        maximum = b


    if maximum % 2 == 0 and maximum // 2 <= minimum:
        maximum = maximum // 2
    elif maximum % 3 == 0 and maximum // 3 <= minimum:
        maximum = maximum // 3
    elif maximum % 5 == 0 and maximum // 5 <= minimum:
        maximum = (maximum // 5) * 4
    else:
        result = -1
        break
    
    result += 1
    if a > b:
        b = minimum 
        a = maximum
    else:
        a = minimum
        b = maximum
        
print(result)
        