Created
December 3, 2020 05:32
-
-
Save erikaderstedt/d776f570ff924c881e94654f5009c150 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| use std::marker::Sized; | |
| use std::ops::{Index,IndexMut}; | |
| use std::cmp::{PartialEq,Eq}; | |
| pub trait GridElement: Sized + PartialEq + Eq + Clone { | |
| fn from_char(c: &char) -> Option<Self>; | |
| } | |
| pub struct Grid<T: GridElement> { | |
| pub rows: usize, | |
| pub cols: usize, | |
| locations: Vec<T>, | |
| } | |
| type Row = usize; | |
| type Column = usize; | |
| #[derive(Clone,Debug)] | |
| pub struct Position { pub row: Row, pub column: Column } | |
| impl Position { | |
| pub fn above(&self) -> Position { Position { row: self.row - 1, column: self.column }} | |
| pub fn below(&self) -> Position { Position { row: self.row + 1, column: self.column }} | |
| pub fn left(&self) -> Position { Position { row: self.row, column: self.column - 1 }} | |
| pub fn right(&self) -> Position { Position { row: self.row, column: self.column + 1 }} | |
| pub fn origin() -> Position { Position { row: 0usize, column: 0 } } | |
| } | |
| impl<T: GridElement> Grid<T> { | |
| pub fn load(lines: &[String]) -> Grid<T> { | |
| let rows = lines.len(); | |
| let locations: Vec<T> = lines | |
| .iter() | |
| .filter(|line| line.chars().count() > 2) | |
| .flat_map(|line| line.chars().filter_map(|c| T::from_char(&c))) | |
| .collect(); | |
| let cols = locations.len() / rows; | |
| assert!(rows * cols == locations.len(), "Grid is not rectangular, perhaps some items won't parse"); | |
| Grid { rows, cols, locations } | |
| } | |
| // Iterate over grid elements of a certain type. | |
| // Iterate over all grid points together with position | |
| // | |
| pub fn neighbors(&self, position: &Position) -> Vec<&T> { | |
| let mut n = Vec::new(); | |
| if position.row > 0 { n.push(&self[&position.above()]) } | |
| if position.row < self.rows - 1 { n.push(&self[&position.below()]) } | |
| if position.column > 0 { n.push(&self[&position.left()]) } | |
| if position.column < self.cols - 1 { n.push(&self[&position.right()]) } | |
| n | |
| } | |
| } | |
| impl<T: GridElement> Index<&Position> for Grid<T> { | |
| type Output = T; | |
| fn index(&self, index: &Position) -> &Self::Output { | |
| &self.locations[index.row * self.cols + index.column] | |
| } | |
| } | |
| impl<T: GridElement> IndexMut<&Position> for Grid<T> { | |
| fn index_mut(&mut self, index: &Position) -> &mut Self::Output { | |
| &mut self.locations[index.row * self.cols + index.column] | |
| } | |
| } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment