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>).
import math
def find_fac_2_3_5(n) :
    pow_2=0
    pow_3=0
    pow_5=0
    #print(n)
    while n%2==0 :
        n=n//2
        pow_2+=1
    while n%3==0 :
        n=n//3
        pow_3+=1
    while n%5==0 :
        n=n//5
        pow_5+=1
    
    
    return pow_2,pow_3,pow_5,n
    
a,b=input().split(" ")
a=int(a)
b=int(b)
k=math.gcd(a,b)
q1,q2,q3,n1=find_fac_2_3_5(a)
e1,e2,e3,n2=find_fac_2_3_5(b)
if n1==n2 :
    li=[]
    li.append(q1)
    li.append(q2)
    li.append(q3)
    li.append(e1)
    li.append(e2)
    li.append(e3)
    li.sort()
    x1,x2,x3,x4,x5,x6=li
    s1=max(x1,x2)
    s2=max(x3,x4)
    s3=max(x5,x6)
    print(s1+s2+s3)
else :
    print("-1")




    





        