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>).
from fractions import Fraction

a, b = list(map(int, input().split()))

result = 0
count = [[]]
sequence = [[]]

def divisors(number, countNum):
    global sequence, count
    array = [2, 3, 5]
    for i in array:
        if number % i == 0:
            if number//i not in sequence[-1]: 
                count[-1].append(countNum+1)
                sequence[-1].append(number//i)
                divisors(number//i, countNum+1)

if a != b:
    divisors(a, 0)
    sequence.append([])
    count.append([])
    divisors(b, 0)

    sequence[0].sort(reverse=True)
    
    for i in range(len(count[0])):
        if sequence[0][i] in sequence[1]:
            result = count[0][i] + count[1][sequence[1].index(sequence[0][i])]
            break
    if result == 0:
        result = -1
else:
    result = 0

print(result)