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>).
queue = []

cur_a, cur_b = [int(x) for x in input().split()]
steps = 0

queue.append((cur_a, cur_b, steps))

while cur_a != cur_b and len(queue) > 0:

    cur_a, cur_b, steps = queue.pop(0)

    if cur_a % 2 == 0:
        next_a = cur_a // 2
        next_b = cur_b
        next_steps = steps + 1
        queue.append( (next_a, next_b, next_steps) )

    if cur_a % 3 == 0:
        next_a = cur_a // 3
        next_b = cur_b
        next_steps = steps + 1
        queue.append( (next_a, next_b, next_steps) )

    if cur_a % 5 == 0:
        next_a = cur_a // 5
        next_b = cur_b
        next_steps = steps + 1
        queue.append( (next_a, next_b, next_steps) )

    if cur_b % 2 == 0:
        next_a = cur_a
        next_b = cur_b // 2
        next_steps = steps + 1
        queue.append( (next_a, next_b, next_steps) )

    if cur_b % 3 == 0:
        next_a = cur_a
        next_b = cur_b // 3
        next_steps = steps + 1
        queue.append( (next_a, next_b, next_steps) )

    if cur_b % 5 == 0:
        next_a = cur_a
        next_b = cur_b // 5
        next_steps = steps + 1
        queue.append( (next_a, next_b, next_steps) )


if cur_a == cur_b:
    print(steps)

else:
    print(-1)
