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>).
def solve(a, b):
    total = 0
    a, b = max(a, b), min(a, b)
    if a != b:
        if a % 15 == 0:
            return min(solve(a-(a*2)//3, b),
                       solve(a-(a*4)//5, b)) + 1
        elif a % 10 == 0:
            return min(solve(a//2, b),
                       solve(a-(a*4)//5, b)) + 1
        elif a % 6 == 0:
            return min(solve(a-(a*2)//3, b),
                       solve(a//2, b)) + 1
        if a % 2 == 0:
            return solve(a//2, b) + 1
        elif a % 3 == 0:
            return solve(a-(a*2)//3, b) + 1
        elif a % 5 == 0:
            return solve(a-(a*4)//5, b) + 1
        else:
            return float('inf')

    return 0


a, b = list(map(int, input().split()))
ans = solve(a, b)
if ans == float('inf'):
    print(-1)
else:
    print(ans)
