Given
- Users should be able to use a code to open a locker and pick up a package
- Delivery guy should be able to find an "optimal" locker for a package
Then
- Free coding from scratch in any language
What I did
I used Vec<Locker> to represent the state.
The interviewer asked if I can improve the code.
I told I could probably use a HashMap (Size -> Locker) if there are standard sizes like (small, medium, large instead of (w,h,d))
Got rejected
trait Volumable {
fn get_volume(&self) -> u32;
}
#[derive(Debug, PartialEq)]
pub struct Package {
w: u32,
h: u32,
d: u32,
}
impl Volumable for Package {
fn get_volume(&self) -> u32 {
self.w * self.h * self.d
}
}
#[derive(Debug, PartialEq)]
pub struct Locker {
w: u32,
h: u32,
d: u32,
code: u32,
occupied: bool,
}
impl Volumable for Locker {
fn get_volume(&self) -> u32 {
self.w * self.h * self.d
}
}
pub fn get_optimal_locker<'a>(
lockers: &'a Vec<Locker>,
package: &Package,
) -> Option<&'a Locker> {
lockers
.iter()
.filter(|l| !l.occupied)
// simplifying here but I wrote a custom fit function to check (w, h, d)
.filter(|l| package.get_volume() <= l.get_volume())
.min_by_key(|l| l.get_volume())
}
pub fn get_locker_by_code<'a>(lockers: &'a Vec<Locker>, code: u32) -> Option<&'a Locker> {
lockers.iter().find(|l| l.code == code)
}Comments (13)
