First day part 1 & 2 solutions

.gitignore

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+/target

Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "aoc2024"
+version = "0.1.0"

Cargo.toml

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+[package]
+name = "aoc2024"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

src/bin/day1.rs

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+use std::collections::{BinaryHeap, HashMap};
+
+use aoc2024::solve;
+
+fn main() {
+    solve(1, part1, part2);
+}
+
+const LINES_IN_INPUT: usize = 1000;
+
+fn part1(input: &str) -> u64 {
+    let (mut list1, mut list2) = (
+        BinaryHeap::<u64>::with_capacity(LINES_IN_INPUT),
+        BinaryHeap::<u64>::with_capacity(LINES_IN_INPUT),
+    );
+    for line in input.lines() {
+        let elements: Vec<u64> = line
+            .split_whitespace()
+            .map(|s| s.parse::<u64>().unwrap())
+            .collect();
+        list1.push(elements[0]);
+        list2.push(elements[1]);
+    }
+    let mut distance = 0u64;
+    while !list1.is_empty() {
+        let (left, right) = (list1.pop().unwrap(), list2.pop().unwrap());
+        distance += left.abs_diff(right);
+    }
+    distance
+}
+
+fn part2(input: &str) -> u64 {
+    let mut list1 = Vec::<u64>::with_capacity(LINES_IN_INPUT);
+    let mut occurences = HashMap::<u64, u64>::with_capacity(LINES_IN_INPUT);
+    for line in input.lines() {
+        let elements: Vec<u64> = line
+            .split_whitespace()
+            .map(|s| s.parse::<u64>().unwrap())
+            .collect();
+        list1.push(elements[0]);
+        let value = occurences.entry(elements[1]).or_default();
+        *value += 1;
+    }
+    let mut score = 0u64;
+    for element in list1 {
+        let element_occurences = occurences.get(&element).map_or(0, |o| *o);
+        score += element * element_occurences;
+    }
+    score
+}

src/lib.rs

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+use std::fmt::Display;
+
+pub fn solve<F, G, FRet, GRet>(day: u8, part1: F, part2: G)
+where
+    FRet: Display,
+    F: FnOnce(&str) -> FRet,
+    GRet: Display,
+    G: FnOnce(&str) -> GRet,
+{
+    let filename = format!("input/day{day}.txt");
+    let input = std::fs::read_to_string(filename).unwrap();
+    println!("Day {day}");
+    println!("Part 1: {}", part1(&input));
+    println!("Part 2: {}", part2(&input));
+}