## 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 etc...
Each number in the series is calculated by the summing of the two previous ones (With the exception of the two first ones which are defined as 0 and 1).
- so fibonacci(2) = 1 (1 + 1)
- and fibonnacci(4) = 3 (1 + 2)
### Notions
- [Primitives ](https://doc.rust-lang.org/stable/rust-by-example/primitives.html )
- [Functions ](https://doc.rust-lang.org/stable/rust-by-example/fn.html )
### 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$
```