Fox Dividing Cheese

两头贪心的小熊有 a，b 两块蛋糕，他们都想要大的那一块的那一块。于是狡猾的狐狸提出一个方案：让狐狸吃掉一些蛋糕，最后使得两块蛋糕大小一样。假如这块蛋糕的重量是 2 的倍数，那么狐狸可以吃掉二分之一；假如蛋糕的重量是 3 的倍数，那么狐狸可以吃掉三分之二；假如蛋糕的重量是 5 的倍数，狐狸可以吃掉五分之四。为了不让狐狸吃掉太多，熊要求以最少的次数将两块蛋糕吃的大小一样，求最小次数。 输入输出格式 输入格式 第一行输入两个整数 $a，b$ ($1 \le a,b \le 10^9$)。 输出格式 若有可分方案，输出最小次数，若无可分方案，输出 `-1`。

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^{9} $ ).

If the fox is lying to the little bears and it is impossible to make the pieces equal, print -1. Otherwise, print the required minimum number of operations. If the pieces of the cheese are initially equal, the required number is 0.

15 20

3

14 8

-1

6 6

0