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>).
a,b=map(int,input().split())
if(a==b):
        print("0")
else:
        def div(n):
                #sprint(n)
                a1,a2,a3=0,0,0
                while(n%5==0):
                        n=n//5
                        #print(n)
                        a1=a1+1
                
                while(n%3==0):
                        n=n//3
                        a2=a2+1
                while(n%2==0):
                        n=n//2
                        a3=a3+1
                #print(n)
                return n,a1,a2,a3
                
                
                
        a,a1,b2,c=div(a)
        #print("lo")
        b,d,e,f=div(b)
        co=abs(a1-d)+abs(b2-e)+abs(c-f)
        if(a!=b):
                print("-1")
        else:
                print(co)
        
                        
                




                
                
