public/subjects/highest

Highest

Instructions

In this exercise a Numbers struct will be given.

These methods have to be written:

• new create a new instance of Number.
• List that returns an array with every number in the struct.
• Latest that returns an Option<u32> with the last added number.
• Highest that return an Option<u32> with the highest number from the list.
• Highest_Three that returns a Vec<u32> with the three highest numbers.

Notions

• Trait iterator

Expected functions

pub fn new(&[u32]) -> Self {}

pub fn list(&self) -> &[u32] {}

pub fn latest(&self) -> Option<u32> {}

pub fn highest(&self) -> Option<u32> {}

pub fn highest_three(&self) -> Vec<u32> {}

Usage

Here is a program to test your function.

use highest::*;

#[derive(Debug)]
struct Numbers<'a> {
    numbers: &'a [u32],
}

fn main() {
    let expected = [30, 500, 20, 70];
    let n = Numbers::new(&expected);
    println!("{:?}", n.list());
    println!("{:?}", n.highest());
    println!("{:?}", n.latest());
    println!("{:?}", n.highest_three());
}

And its output:

$ cargo run
[30, 500, 20, 70]
Some(500)
Some(70)
[500, 70, 30]
$