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 five(x):
    c=0
    while x%5==0:
        c+=1
        x=x//5
    return c
def two(x):
    c=0
    while x%2==0:
        c+=1
        x=x//2
    return c
def three(x):
    c=0
    while x%3==0:
        c+=1
        x=x//3
    return c

a,b=map(int,input().split())
if a==b:
    print(0)
else:
    a1=a//(2**two(a)*3**three(a)*5**five(a))
    b1=b//(2**two(b)*3**three(b)*5**five(b))
    if a1!=b1:
        print(-1)
    else:
        p=abs(two(a)-two(b))+abs(three(a)-three(b))+abs(five(a)-five(b))
        print(p)












