day 1

2024/day01/src/lib.rs

@@ -0,0 +1,75 @@
+use helper::{Day, IteratorExt, Variants};
+
+pub fn main() {
+    helper::main::<Day01>(include_str!("../input.txt"));
+}
+
+struct Day01;
+
+helper::define_variants! {
+    day => crate::Day01;
+    part1 {
+        basic => crate::part1;
+    }
+    part2 {
+        basic => crate::part2;
+    }
+}
+
+impl Day for Day01 {
+    fn part1() -> Variants {
+        part1_variants!(construct_variants)
+    }
+
+    fn part2() -> Variants {
+        part2_variants!(construct_variants)
+    }
+}
+
+fn parse(input: &str) -> (Vec<u64>, Vec<u64>) {
+    input
+        .lines()
+        .map(|line| {
+            line.split_ascii_whitespace()
+                .map(|part| part.parse::<u64>().unwrap())
+                .collect_array::<2>()
+                .unwrap()
+        })
+        .map(|[a, b]| (a, b))
+        .unzip()
+}
+
+fn part1(input: &str) -> u64 {
+    let (mut a, mut b) = parse(input);
+
+    a.sort();
+    b.sort();
+
+    a.into_iter().zip(b).map(|(a, b)| a.abs_diff(b)).sum()
+}
+
+fn part2(input: &str) -> u64 {
+    let (left, right) = parse(input);
+
+    let mut score = 0;
+
+    for number in left {
+        let occurs = right.iter().filter(|right| **right == number).count();
+        score += number * (occurs as u64);
+    }
+
+    score
+}
+
+helper::tests! {
+    day01 Day01;
+    part1 {
+        small => 11;
+        default => 2580760;
+    }
+    part2 {
+        small => 31;
+        default => 25358365;
+    }
+}
+helper::benchmarks! {}