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 sys
import math
import collections
import bisect
def get_ints(): return map(int, sys.stdin.readline().strip().split())
def get_list(): return list(map(int, sys.stdin.readline().strip().split()))
def get_string(): return sys.stdin.readline().strip()
for t in range(1):
    a,b=get_ints()
    two=0
    three=0
    five=0
    while a%2==0:
        a=a//2
        two+=1
    while a%3==0:
        a=a//3
        three+=1
    while a%5==0:
        a=a//5
        five+=1
    while b%2==0:
        b=b//2
        two-=1
    while b%3==0:
        b=b//3
        three-=1
    while b%5==0:
        b=b//5
        five-=1
    if a==b:
        print(abs(two)+abs(three)+abs(five))
    else:
        print(-1)