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## lunch_queue
### Instructions
You will have to create an API to organize a queue of people.
Using the given code create the following functions:
- `new` that will initialize the `Queue`.
- `add` that receives the person's information, so it can be added to the `Queue`
- `invert_queue` that invert the queue of persons
- `rm`, that will remove the person that finished ordering their food.
The method for organizing the manipulation of a data structure should be a
FIFO (first in first out) process. This function should return a tuple wrapped in an `Option`
with the information of that person
- `search`, that return a tuple with the information of a given person `id`.
You must also create a type called `Link` this will be the connection of the structures `Queue` and `Person`.
Do not forget that this will be a recursion type and it must point to `None` if there is no persons.
### Expected Function
```rust
pub struct Queue {
pub node: Link,
}
pub type Link =
pub struct Person {
pub id: i32,
pub name: String,
}
impl Queue {
pub fn new() -> Queue {}
pub fn add(&mut self, t: String, name: String) {}
pub fn invert_queue(&mut self) {}
pub fn rm(&mut self) -> Option<String> {}
pub fn search(&self) -> Option<(String, String)> {}
}
```
### Usage
Here is a program to test your function
```rust
fn main() {
let mut list = Queue::new();
list.add(String::from("Marie"), 20);
list.add(String::from("Monica"), 15);
list.add(String::from("Ana"), 5);
list.add(String::from("Alice"), 35);
println!("{:?}", list);
println!("{:?}", list.search("Marie"));
println!("{:?}", list.search("Alice"));
println!("{:?}", list.search("someone"));
println!("removed {:?}", list.rm());
println!("list {:?}", list);
println!("invert {:?}", list.invert_queue());
}
```
And its output:
```console
student@ubuntu:~/[[ROOT]]/test$ cargo run
Queue { node: Some(Person { name: "Alice", discount: 35, next_person: Some(Person { name: "Ana", discount: 5, next_person: Some(Person { name: "Monica", discount: 15, next_person: Some(Person { name: "Marie", discount: 20, next_person: None }) }) }) }) }
Some(("Marie", 20))
Some(("Alice", 35))
None
removed Some(("Marie", 20))
removed Some(("Monica", 15))
list Queue { node: Some(Person { name: "Alice", discount: 35, next_person: Some(Person { name: "Ana", discount: 5, next_person: None }) }) }
inverted list Queue { node: Some(Person { name: "Ana", discount: 5, next_person: Some(Person { name: "Alice", discount: 35, next_person: None }) }) }
student@ubuntu:~/[[ROOT]]/test$
```
### Notions
- https://doc.rust-lang.org/rust-by-example/custom_types/enum.html
- https://doc.rust-lang.org/book/ch15-01-box.html
- https://doc.rust-lang.org/std/option/
- https://doc.rust-lang.org/book/ch15-01-box.html