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
input = sys.stdin.readline

############ ---- Input Functions ---- ############
def inp():
    return(int(input()))
def inlt():
    return(list(map(int,input().split())))
def insr():
    s = input()
    return(list(s[:len(s) - 1]))
def invr():
    return(map(int,input().split()))
############ ---- Input Functions ---- ############

def Fox_Dividing_Cheese():
    def power_of_2(num):
        power = 0

        while num % 2 == 0:
            power += 1
            num = num//2 
        
        return power
    
    def power_of_3(num):
        power = 0 
        
        while num % 3 == 0:
            power += 1 
            num = num//3

        return power 
    
    def power_of_5(num):
        power = 0 

        while num % 5 == 0:
            power += 1 
            num = num//5 
        
        return power 
    
    a,b = invr()
    a1 = power_of_2(a)
    a2 = power_of_3(a)
    a3 = power_of_5(a)
    b1 = power_of_2(b)
    b2 = power_of_3(b)
    b3 = power_of_5(b)
    
    #print(a1,a2,a3,b1,b2,b3)
    partial_num_a = (2**a1)*(3**a2)*(5**a3)
    partial_num_b = (2**b1)*(3**b2)*(5**b3)
    x = a//partial_num_a
    y = b//partial_num_b

    if x != y:
        print(-1)
        return 
    else:
        power_of_2_dist = abs(a1-b1)
        power_of_3_dist = abs(a2-b2)
        power_of_5_dist = abs(a3-b3)
        print(power_of_2_dist + power_of_3_dist + power_of_5_dist)
        return

Fox_Dividing_Cheese()