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 reduce(a):
    if(a%2 == 0):
        return a//2
    elif(a%3 == 0):
        return a//3
    elif(a%5 == 0):
        return a//5
    else:
        return -1

a,b = map(int,input().split(' '))
cnt = 0
while(1):
    if(a == b):
        break
    if(a>b):
        a = reduce(a)
        if(a == -1):
            break
    else:
        b = reduce(b)
        if(b == -1):
            break
    cnt += 1

if(a == -1 or b == -1):
    print(-1)
else:
    print(cnt)    
