Parse day 22 bricks

day22/src/day22.rs

@@ -1,3 +1,71 @@
+use std::{
+ convert::TryInto,
+ env,
+ fs,
+ fmt,
+ process,
+ str::FromStr,
+};
+
+fn parse_delimited<T, const N: usize>(raw: &str, delimiter: &str) -> Result<[T; N], String>
+where
+ T: FromStr,
+ T::Err: fmt::Display {
+ raw
+ .split(delimiter)
+ .map(|s| s.parse().map_err(|e| format!("Could not parse '{s}': {e}")))
+ .collect::<Result<Vec<T>, _>>()?
+ .try_into()
+ .map_err(|e| format!("Could not parse '{raw}': Expected {N} element(s)"))
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
+struct Vec3 {
+ x: i32,
+ y: i32,
+ z: i32,
+}
+
+impl Vec3 {
+ pub fn new(x: i32, y: i32, z: i32) -> Self {
+ Self { x, y, z }
+ }
+}
+
+impl FromStr for Vec3 {
+ type Err = String;
+
+ fn from_str(raw: &str) -> Result<Self, String> {
+ let [x, y, z] = parse_delimited(raw, ",")?;
+ Ok(Self { x, y, z })
+ }
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
+struct Brick {
+ start: Vec3,
+ end: Vec3,
+}
+
+impl FromStr for Brick {
+ type Err = String;
+
+ fn from_str(raw: &str) -> Result<Self, String> {
+ let [start, end] = parse_delimited(raw, "~")?;
+ Ok(Self { start, end })
+ }
+}
+
 fn main() {
- println!("Hello world!");
+ let args: Vec<String> = env::args().collect();
+ if args.len() == 1 {
+ println!("Usage: {} <path to input>", args[0]);
+ process::exit(1);
+ }
+ let raw_input = fs::read_to_string(&args[1]).unwrap();
+ let bricks: Vec<Brick> = raw_input.lines()
+ .map(Brick::from_str)
+ .collect::<Result<_, _>>()
+ .unwrap();
+ println!("{bricks:?}");
 }