Initial commit: Day 1 & 2

.editorconfig

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+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = false
+insert_final_newline = true

.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 = "aoc"
+version = "0.1.0"
+dependencies = [
+ "itertools",
+]
+
+[[package]]
+name = "either"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e78d4f1cc4ae33bbfc157ed5d5a5ef3bc29227303d595861deb238fcec4e9457"
+
+[[package]]
+name = "itertools"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69ddb889f9d0d08a67338271fa9b62996bc788c7796a5c18cf057420aaed5eaf"
+dependencies = [
+ "either",
+]

Cargo.toml

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+[package]
+name = "aoc"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+itertools = "0.10.1"

inputs/.gitignore

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+*
+!.gitignore

src/day01.rs

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+use itertools::Itertools;
+
+const INPUT: &str = include_str!("../inputs/01");
+
+fn input_numbers() -> impl Iterator<Item = usize> {
+    INPUT.lines().filter_map(|s| s.parse::<usize>().ok())
+}
+
+fn part_1() -> usize {
+    input_numbers()
+        .tuple_windows()
+        .filter(|(a, b)| b > a)
+        .count()
+}
+
+fn part_2() -> usize {
+    input_numbers()
+        .tuple_windows()
+        .map(|(a, b, c)| a + b + c)
+        .tuple_windows()
+        .filter(|(a, b)| b > a)
+        .count()
+}
+
+pub fn main() {
+    println!("Day 1:");
+    println!("  Part 1: {}", part_1());
+    println!("  Part 2: {}", part_2());
+}

src/day02.rs

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+const INPUT: &str = include_str!("../inputs/02");
+
+fn get_instructions() -> impl Iterator<Item = (&'static str, isize)> {
+    INPUT
+        .lines()
+        .filter_map(|s| s.split_once(' '))
+        .filter_map(|(op, n)| n.parse::<isize>().ok().map(|n| (op, n)))
+}
+
+fn part_1() -> isize {
+    let x: isize = get_instructions()
+        .filter(|(op, _)| *op == "forward")
+        .map(|(_, n)| n)
+        .sum();
+
+    let y: isize = get_instructions()
+        .filter_map(|(op, n)| match op {
+            "up" => Some(-n),
+            "down" => Some(n),
+            _ => None,
+        })
+        .sum();
+
+    x * y
+}
+
+fn part_2() -> isize {
+    let mut x = 0isize;
+    let mut depth = 0isize;
+    let mut aim = 0isize;
+
+    for (op, n) in get_instructions() {
+        match op {
+            "forward" => {
+                x += n;
+                depth += n * aim;
+            }
+            "down" => aim += n,
+            "up" => aim -= n,
+            _ => unreachable!(),
+        }
+    }
+
+    x * depth
+}
+
+pub fn main() {
+    println!("Day 2:");
+    println!("  Part 1: {}", part_1());
+    println!("  Part 2: {}", part_2());
+}

src/main.rs

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+mod day01;
+mod day02;
+
+fn main() {
+    day01::main();
+    day02::main();
+}