## fibonacci2

### Instructions

Complete the body of the function `fibonacci`.

This functions receives a number n and returns the nth number in the fibonacci series.

The Fibonacci Series starts like this: 0, 1, 1, 2, 3, 5, 8, 13... so fibonacci(2) = 1 and fibonnacci(4) = 3


### Expected function

```rust
 fn fibonacci(n: u32) -> u32 {

 }
```

### Usage

Here is a possible test for your function:

```rust
use fibonacci2::fibonacci;

fn main() {
    println!("The element in the position {} in fibonacci series is {}",2,  fibonacci(2));
    println!("The element in the position {} in fibonacci series is {}",4, fibonacci(4));
    println!("The element in the position {} in fibonacci series is {}",22, fibonacci(22));
    println!("The element in the position {} in fibonacci series is {}", 20, fibonacci(20));
}
```

And its output:

```console
student@ubuntu:~/[[ROOT]]/test$ cargo run
The element in the position 2 in fibonacci series is 1
The element in the position 4 in fibonacci series is 3
The element in the position 22 in fibonacci series is 17711
The element in the position 20 in fibonacci series is 6765
student@ubuntu:~/[[ROOT]]/test$
```