readying 2022 to merge

2022/day4/Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day4"
+version = "0.1.0"

2022/day4/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "day4"
+version.workspace = true
+edition.workspace = true
+authors.workspace = true
+repository.workspace = true
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+nom.workspace = true

2022/day4/src/main.rs

@@ -0,0 +1,79 @@
+#![warn(clippy::all, clippy::pedantic)]
+
+use std::fs;
+
+use nom::{
+    bytes::complete::tag,
+    character::complete::{self, newline},
+    multi::separated_list0,
+    sequence::separated_pair,
+};
+
+fn parse_range(input: &str) -> nom::IResult<&str, (i32, i32)> {
+    separated_pair(complete::i32, tag("-"), complete::i32)(input)
+}
+fn parse_line(input: &str) -> nom::IResult<&str, ((i32, i32), (i32, i32))> {
+    separated_pair(parse_range, tag(","), parse_range)(input)
+}
+fn process_input(input: &str) -> nom::IResult<&str, Vec<((i32, i32), (i32, i32))>> {
+    separated_list0(newline, parse_line)(input)
+}
+
+fn part1(input: &str) -> String {
+    do_part(input, |(a, b)| {
+        i32::from((a.0 <= b.0 && a.1 >= b.1) || (a.0 >= b.0 && a.1 <= b.1))
+    })
+}
+fn part2(input: &str) -> String {
+    do_part(input, |(a, b)| {
+        i32::from(
+            (a.0 >= b.0 && a.0 <= b.1)
+                || (a.1 >= b.0 && a.1 <= b.1)
+                || (b.0 >= a.0 && b.0 <= a.1)
+                || (b.1 >= a.0 && b.1 <= a.1),
+        )
+    })
+}
+
+fn do_part(input: &str, f: impl Fn((&(i32, i32), &(i32, i32))) -> i32) -> String {
+    let (_, ranges) = process_input(input).unwrap();
+    ranges
+        .iter()
+        .map(|(a, b)| f((a, b)))
+        .fold(0, |mut acc: i32, x: i32| {
+            acc += x;
+            acc
+        })
+        .to_string()
+}
+fn main() -> std::io::Result<()> {
+    //Read in file
+    let file = fs::read_to_string("input")?;
+
+    println!("Part 1: {}", part1(&file));
+    println!("Part 2: {}", part2(&file));
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    const INPUT: &str = "2-4,6-8
+2-3,4-5
+5-7,7-9
+2-8,3-7
+6-6,4-6
+2-6,4-8";
+
+    #[test]
+    fn part1_works() {
+        assert_eq!(part1(INPUT), "2")
+    }
+
+    #[test]
+    fn part2_works() {
+        assert_eq!(part2(INPUT), "4")
+    }
+}