# Task
 Mobius function - an important function in number theory. For each given n, it only has 3 values:
```
0  -- if n divisible by square of a prime. Such as: 4, 8, 9
1  -- if n not divisible by any square of a prime 
        and have even number of prime factor. Such as: 6, 10, 21
-1 -- otherwise. Such as: 3, 5, 7, 30```
Your task is to find mobius(`n`)

# Input/Output


 - `[input]` integer `n`


 `2 <= n <= 1e12`


 - `[output]` an integer