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>).
def gcd(a, b):
    if b == 0:
        return a
    return gcd(b, a % b)

cheese1, cheese2 = list(int(num) for num in input().split(" "))

max = gcd(cheese1, cheese2)
aux_cheese1 = cheese1 / max
aux_cheese2 = cheese2 / max

divisors = [2, 3, 5]
exp_cheese1 = [0, 0, 0]
exp_cheese2 = [0, 0, 0]
operations = 0

final_cheese1 = max
final_cheese2 = max
if max != 1:
    for i in range(3):
        divisor = divisors[i]
        times_cheese1 = 0
        times_cheese2 = 0
        while aux_cheese1 % divisor == 0:
            aux_cheese1 /= divisor
            times_cheese1 += 1
        while aux_cheese2 % divisor == 0:
            aux_cheese2 /= divisor
            times_cheese2 += 1

        exp_cheese1[i] = times_cheese1
        exp_cheese2[i] = times_cheese2

        final_cheese1 *= divisor ** times_cheese1
        final_cheese2 *= divisor ** times_cheese2

        operations += times_cheese1 + times_cheese2

    if final_cheese2 != cheese2 or final_cheese1 != cheese1:
        operations = -1
else:
    operations = -1

print(operations)


 	      					  	  	    	 	    	