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>).
c = list(map(int, input().split()))
count = 1


def cheese_split(c1, c2, count):
    found = False
    div = 0

    if c1 == c2:
        return True, count - 1
    elif c1 > c2:
        for i in [2, 3, 5]:
            if not found:
                if c1 % i == 0:
                    found, div = cheese_split(c1 / i, c2, count + 1)
            else:
                return True, div
        return False, -1
    else:
        for i in [2, 3, 5]:
            if not found:
                if c2 % i == 0:
                    found, div = cheese_split(c1, c2 / i, count + 1)
            else:
                return True, div
        return False, -1


found, div = cheese_split(c[0], c[1], count)
print(div)
