started work on day 4

day4/Cargo.lock

···
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "day4"
+version = "0.1.0"

day4/Cargo.toml

···
+[package]
+name = "day4"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

day4/shortinput.txt

···
+..@@.@@@@.
+@@@.@.@.@@
+@@@@@.@.@@
+@.@@@@..@.
+@@.@@@@.@@
+.@@@@@@@.@
+.@.@.@.@@@
+@.@@@.@@@@
+.@@@@@@@@.
+@.@.@@@.@.

day4/src/main.rs

···
+use std::fmt::Display;
+use std::ops::{Add, Sub};
+
+struct Warehouse {
+    layout: Vec<Vec<Option<char>>>,
+    width: u16,
+    height: u16,
+}
+
+impl Warehouse {
+    fn new(width: u16, height: u16) -> Warehouse {
+        Warehouse {
+            layout: vec![vec![None; width as usize]; height as usize],
+            width: width,
+            height: height,
+        }
+    }
+
+    fn get(&self, x: u16, y: u16) -> Option<char> {
+        *self.layout.get(y as usize)?.get(x as usize)?
+    }
+
+    fn set(&mut self, x: u16, y: u16, value: char) {
+        // TODO : This is not a complete check, could cause issues
+        if y < self.layout.len() as u16 && x < self.layout[0].len() as u16 {
+            self.layout[y as usize][x as usize] = Some(value);
+        }
+    }
+
+    fn load_from_file(filename: &str) -> Warehouse {
+        let contents = std::fs::read_to_string(filename).expect("Failed to read file");
+        let width = contents.lines().next().unwrap().len() as u16;
+        let height = contents.lines().count() as u16;
+        let layout = contents
+            .lines()
+            .map(|line| line.chars().map(|c| Some(c)).collect())
+            .collect();
+        Warehouse {
+            layout,
+            width,
+            height,
+        }
+    }
+
+    fn count_neighbors(&self, x: u16, y: u16) -> Option<u8> {
+        println!("Counting neighbors at ({}, {})", x, y);
+        let mut neighbors = 0u8;
+        for n_y in y.checked_sub(1).unwrap_or(0)..y.add(2).min(self.height) {
+            for n_x in x.checked_sub(1).unwrap_or(0)..x.add(2).min(self.width) {
+                if n_y == y && n_x == x {
+                    continue;
+                }
+                if let Some(cell) = self.get(n_x, n_y) {
+                    if cell == '@' {
+                        neighbors += 1;
+                        println!("Neighbor found at ({}, {})", n_x, n_y);
+                    }
+                }
+            }
+        }
+        Some(neighbors)
+    }
+}
+
+impl Display for Warehouse {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        for row in &self.layout {
+            for cell in row {
+                match cell {
+                    Some(c) => write!(f, "{}", c)?,
+                    None => write!(f, ".")?,
+                }
+            }
+            writeln!(f)?;
+        }
+        Ok(())
+    }
+}
+
+fn main() {
+    //    let printer_department = Warehouse::new(10, 10);
+    let printer_department = Warehouse::load_from_file("shortinput.txt");
+    let mut accessible_rolls = 0;
+    // DONT LIKE THESE CLONES!!
+    // Need to figure out how to make an iterator out of a reference
+    for (x, row) in printer_department.layout.clone().into_iter().enumerate() {
+        for (y, cell) in row.clone().into_iter().enumerate() {
+            match cell {
+                Some(c) => {
+                    if printer_department
+                        .count_neighbors(x as u16, y as u16)
+                        .unwrap_or(0)
+                        < 4
+                    {
+                        accessible_rolls += 1;
+                        println!("Accessible roll found at ({}, {})", x, y);
+                    }
+                }
+                None => continue,
+            }
+        }
+    }
+    println!("There are {} accessible rolls", accessible_rolls);
+    let neighbors = printer_department.count_neighbors(0, 0);
+    println!("Neighbors at (0, 0): {}", neighbors.unwrap());
+    println!("{}", printer_department);
+}