solve: day5

Author: tom-anders

Cargo.toml

@@ -2,7 +2,7 @@
 resolver = "2"
 members = [
     "aoc_lib/aoc_derive",
-    "aoc_lib/utils", "day1", "day2", "day3", "day4",
+    "aoc_lib/utils", "day1", "day2", "day3", "day4", "day5",
 ]
 
 [workspace.dependencies]

aoc_lib

@@ -0,0 +1,18 @@
+[package]
+name = "day5"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+aoc_derive.path = '../aoc_lib/aoc_derive'
+utils.path = '../aoc_lib/utils'
+derive_more.workspace = true
+itertools.workspace = true
+lazy-regex.workspace = true
+parse-display.workspace = true
+rayon.workspace = true
+regex.workspace = true
+num.workspace = true
+
+[dev-dependencies]
+pretty_assertions.workspace = true

day5/Cargo.toml

@@ -0,0 +1,64 @@
+use std::ops::RangeInclusive;
+
+use aoc_derive::aoc_main;
+use itertools::Itertools;
+use utils::*;
+
+fn part2(mut ranges: Vec<RangeInclusive<usize>>) -> usize {
+    ranges.sort_by_key(|r| *r.start());
+    loop {
+        let prev = ranges.len();
+        let mut i = 0;
+        while i < ranges.len() - 1 {
+            if ranges[i].end() >= ranges[i + 1].start() {
+                ranges[i] = *ranges[i].start()..=(*ranges[i + 1].end().max(ranges[i].end()));
+                ranges.remove(i + 1);
+            } else {
+                i += 1;
+            }
+        }
+
+        if ranges.len() == prev {
+            return ranges.iter().map(|range| range.try_len().unwrap()).sum();
+        }
+    }
+}
+
+#[aoc_main]
+fn solve(input: Input) -> impl Into<Solution> {
+    let (ranges, ingredients) = input.raw.split_once("\n\n").unwrap();
+    let ranges = ranges
+        .lines()
+        .map(|line| {
+            let (start, end) = line.split('-').collect_tuple().unwrap();
+            start.parse_usize()..=end.parse_usize()
+        })
+        .collect_vec();
+    let ingredients = ingredients.lines().map(|line| line.parse::<usize>().unwrap()).collect_vec();
+
+    (ingredients.iter().filter(|i| ranges.iter().any(|r| r.contains(i))).count(), part2(ranges))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_examples() {
+        use utils::assert_example;
+        assert_example!(
+            r#"3-5
+10-14
+16-20
+12-18
+
+1
+5
+8
+11
+17
+32"#,
+            3,
+            14
+        );
+    }
+}