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>).
cntOne,cntTwo = list(map(int,input().split()))
result = 0
counter = 0
for i in range(cntOne):
    if cntOne == cntTwo:
        break
    if cntOne < cntTwo:
        if cntTwo % 2 == 0:
            cntTwo //= 2
        elif cntTwo % 3 == 0:
            cntTwo //= 3
        elif cntTwo % 5 == 0:
            cntTwo //= 5
        result += 1
    else:
        if cntOne % 2 == 0:
            cntOne //= 2
        elif cntOne % 3 == 0:
            cntOne //= 3
        elif cntOne % 5 == 0:
            cntOne //= 5
        result += 1
if cntTwo != cntOne or cntTwo <= 1 or cntOne <= 1:
    print('-1')
else:
    print(result)