advent-of-code/2021/src/grid.rs
2021-12-15 18:07:19 +01:00

127 lines
3.9 KiB
Rust

pub mod cell;
pub mod direction;
pub mod position;
pub use direction::*;
use itertools::join;
pub use position::*;
use std::{collections::HashMap, fmt::Display, hash::BuildHasher};
#[allow(clippy::len_without_is_empty)] // I mainly have this for assertions in benchmarks
pub trait Grid<T, const D: usize> {
fn get(&self, pos: &PositionND<D>) -> Option<&T>;
fn insert<Pos: Into<PositionND<D>>>(&mut self, pos: Pos, element: T);
fn len(&self) -> usize;
}
#[derive(Debug, Clone, PartialEq)]
pub struct HashGrid<T: Default, const D: usize> {
pub fields: HashMap<PositionND<D>, T>,
}
impl<T: Default, const D: usize> Grid<T, D> for HashGrid<T, D> {
fn get(&self, pos: &PositionND<D>) -> Option<&T> {
self.fields.get(pos)
}
fn insert<Pos: Into<PositionND<D>>>(&mut self, pos: Pos, t: T) {
self.fields.insert(pos.into(), t);
}
fn len(&self) -> usize {
self.fields.len()
}
}
impl<T: Default + Copy, const D: usize> HashGrid<T, D> {
pub fn from_bytes_2d<F: FnMut(u8) -> T + Copy>(raw: &str, mut f: F) -> HashGrid<T, 2> {
raw.lines()
.enumerate()
.flat_map(move |(y, l)| l.bytes().enumerate().map(move |(x, c)| (PositionND { points: [x as i64, y as i64] }, f(c))))
.collect()
}
}
impl<T: Default, const D: usize> std::iter::FromIterator<(PositionND<D>, T)> for HashGrid<T, D> {
fn from_iter<I: IntoIterator<Item = (PositionND<D>, T)>>(iter: I) -> Self {
HashGrid { fields: iter.into_iter().collect() }
}
}
#[derive(Debug, Clone, PartialEq)]
pub struct VecGrid<T> {
pub fields: Vec<Vec<T>>,
}
impl<T> Grid<T, 2> for VecGrid<T> {
fn get(&self, pos: &PositionND<2>) -> Option<&T> {
self.fields.get(pos.points[0] as usize)?.get(pos.points[1] as usize)
}
fn insert<Pos: Into<PositionND<2>>>(&mut self, pos: Pos, element: T) {
let PositionND { points: [x, y] } = pos.into();
self.fields[x as usize][y as usize] = element;
}
fn len(&self) -> usize {
self.fields.len()
}
}
impl<T: Copy> VecGrid<T> {
pub fn from_bytes_2d<F: FnMut(u8) -> T + Copy>(raw: &str, mut f: F) -> VecGrid<T> {
VecGrid { fields: raw.lines().map(|l| l.bytes().map(|c| f(c)).collect()).collect() }
}
}
struct Boundaries {
x_min: i64,
x_max: i64,
y_min: i64,
y_max: i64,
}
fn get_boundaries(input: &[&PositionND<2>]) -> Boundaries {
let x_min = input.iter().min_by_key(|k| k.points[0]).map(|p| p.points[0]).unwrap_or(0);
let x_max = input.iter().max_by_key(|k| k.points[0]).map(|p| p.points[0]).unwrap_or(0);
let y_min = input.iter().min_by_key(|k| k.points[1]).map(|p| p.points[1]).unwrap_or(0);
let y_max = input.iter().max_by_key(|k| k.points[1]).map(|p| p.points[1]).unwrap_or(0);
Boundaries { x_min, x_max, y_min, y_max }
}
pub fn draw_ascii<T: Display + Default, S: BuildHasher>(coordinates: &HashMap<PositionND<2>, T, S>) -> String {
let b = get_boundaries(&coordinates.keys().collect::<Vec<_>>());
join(
(b.y_min..=b.y_max).rev().map(|y| {
(b.x_min..=b.x_max)
.map(|x| coordinates.get(&PositionND { points: [x, y] }).unwrap_or(&T::default()).to_string())
.collect::<String>()
}),
"\n",
)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_add() {
assert_eq!(PositionND::from([0, 2]) + PositionND::from([-1, 0]), [-1, 2].into());
assert_eq!(PositionND::from([0, -1]) + PositionND::from(Direction::Up), [0, 0].into());
}
#[test]
fn test_sub() {
assert_eq!(PositionND::from([0, 2]) - PositionND::from([-1, 0]), [1, 2].into());
assert_eq!(PositionND::from([0, -1]) - PositionND::from([0, -1]), [0, 0].into());
}
#[test]
fn test_mul() {
assert_eq!(PositionND::from([0, 2]) * 5, [0, 10].into());
assert_eq!(PositionND::from([0, -1]) * -2, [0, 2].into());
}
}