## Sign

### Instructions

Create a function named `sign` that takes one number argument; returning `1` if the number is positive, `-1` if the number is negative and `0` if the number is exactly 0.
> You must not just use `Math.sign`, make your own.

Create a function named `sameSign` that takes 2 numbers as arguments and returns `true` if they both have the same sign, or false otherwise.

### Notions

- [Functions](https://nan-academy.github.io/js-training/examples/functions.js)
- [If-else](https://nan-academy.github.io/js-training/examples/if-else.js)
- [Math.sign](https://devdocs.io/javascript/global_objects/math/sign)

### Code provided

> The provided code will be added to your solution, and does not need to be submitted.

```js
Math.sign = undefined
```
