public/subjects/box_recursion

box_recursion

Instructions

Using the given code create the following functions:

• new that will initialize the WorkEnvironment as None
• add_worker, that receives two strings, one being the type of worker and the other the name of the worker.
• remove_worker, that removes the last worker that was placed in the WorkEnvironment, this functions should return a Option with the name of the worker.
• search_worker, that return a tuple with the name and type of worker.

You must also create a type called Link this will be the connection of the structures WorkEnvironment and Worker. Do not forget that this will be a recursion type and it must point to None if there is no workers.

Expected Function

pub struct WorkEnvironment {
    pub grade: Link,
}

pub type Link = 

pub struct Worker {
    pub worker_type: String,
    pub worker_name: String,
    pub next_worker: Link,
}

impl WorkEnvironment {
    pub fn new() -> WorkEnvironment {}
    pub fn add_worker(&mut self, t: String, name: String) {}
    pub fn remove_worker(&mut self) -> Option<String> {}
    pub fn search_worker(&self) -> Option<(String, String)> {}
}

Usage

Here is a program to test your function

fn main() {
    let mut list = WorkEnvironment::new();
    list.add_worker(String::from("CEO"), String::from("Marie"));
    list.add_worker(String::from("Manager"), String::from("Monica"));
    list.add_worker(String::from("Normal Worker"), String::from("Ana"));
    list.add_worker(String::from("Normal Worker"), String::from("Alice"));
    println!("{:?}", list);

    println!("{:?}", list.search_worker());

    list.remove_worker();
    list.remove_worker();
    list.remove_worker();
    list.remove_worker();
    println!("{:?}", list);
}

And its output:

student@ubuntu:~/[[ROOT]]/test$ cargo run
WorkEnvironment { grade: Some(Worker { worker_type: "Normal Worker", worker_name: "Alice", next_worker: Some(Worker { worker_type: "Normal Worker", worker_name: "Ana", next_worker: Some(Worker { worker_type: "Manager", worker_name: "Monica", next_worker: Some(Worker { worker_type: "CEO", worker_name: "Marie", next_worker: None }) }) }) }) }
Some(("Alice", "Normal Worker"))
WorkEnvironment { grade: 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