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 process(a, b, step):

    if(a==b):
        return step
    steps = a+b
    changed = False
    if(a>b):
        if(a%5==0):
            val = process(a//5, b, step+1)
            if val!=-1:
                steps = min(steps, val)
                changed = True
        elif(a%3==0):
            val = process(a//3, b, step+1)
            if val!=-1:
                steps = min(steps, val)
                changed = True
        elif(a%2==0):
            val = process(a//2, b, step+1)
            if val!=-1:
                steps = min(steps, val)
                changed = True
        else :
            return -1
    else:
        if(b%5==0):
            val = process(a, b//5, step+1)
            if val!=-1:
                steps = min(steps, val)
                changed = True
        elif(b%3==0):
            val = process(a, b//3, step+1)
            if val!=-1:
                steps = min(steps, val)
                changed = True
        elif(b%2==0):
            val = process(a, b//2, step+1)
            if val!=-1:
                steps = min(steps, val)
                changed = True
        else :
            return -1
    if not changed:
        return -1
    else :
        return steps

    

a,b = map(int, input().split())
print(process(a,b,0))
