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 math import gcd


def factorize(n):
    count = [0, 0, 0]
    while n != 1:
        if (n & 1) == 0:
            count[0] += 1
            n //= 2
        elif n % 3 == 0:
            count[1] += 1
            n //= 3
        elif n % 5 == 0:
            n //= 5
            count[2] += 1
        else:
            break
    return count, n


def diff(x, y):
    total = 0
    for a, b in zip(x, y):
        total += abs(a - b)
    return total


def main():
    a, b = map(int, input().split(" "))
    if a == b:
        return 0

    x,rem1 = factorize(a)
    y, rem2 = factorize(b)

    if rem1 != rem2:
        return -1
    else:
        return diff(x, y)


print(main())
