# Which Number Is Not like the Others?
by Helen Yu
tags: numbers, arrays, algorithms

## Summary
> Create a function that takes an array of numbers and return the number that's unique.
> Examples
> unique([3, 3, 3, 7, 3, 3]) ➞ 7
> unique([0, 0, 0.77, 0, 0]) ➞ 0.77
> unique([0, 1, 1, 1, 1, 1, 1, 1]) ➞ 0
> Notes
> Test cases will always have exactly one unique number while all others are the same.

## Instructions
Create a function that takes an array of numbers and return the number that's unique.

### Examples
```
unique([3, 3, 3, 7, 3, 3]) ➞ 7

unique([0, 0, 0.77, 0, 0]) ➞ 0.77

unique([0, 1, 1, 1, 1, 1, 1, 1]) ➞ 0
```

### Notes
Test cases will always have exactly one unique number while all others are the same.