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 fac(n,l) : 
    while n > 1 : 
        cr = n
        if not n%5 : l.append(5); n //= 5
        if not n%3 : l.append(3); n //= 3
        if not n%2 : l.append(2); n//= 2
        if n == cr : break 
    return n
def sol() : 
    a,b = map(int,input().split()); from math import gcd; g = gcd(a,b); af = a//g; bf = b//g; l = list(); af = fac(af,l); bf = fac(bf,l); l = [i for i in l if i!=1]
    if af==1 and bf==1 :print(len(l))
    else : print(-1)
sol()