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>).
m,n=map(int,input().split())
a2,b2,a3,b3,a5,b5=0,0,0,0,0,0
while m%2==0:
    m//=2
    a2+=1
while m%3==0:
    m//=3
    a3+=1
while m%5==0:
    m//=5
    a5+=1
while n%2==0:
    n//=2
    b2+=1
while n%3==0:
    n//=3
    b3+=1
while n%5==0:
    n//=5
    b5+=1
if m==n:
    print(abs(a2-b2)+abs(a3-b3)+abs(a5-b5))
else:
    print(-1)