commit 51459c17c6cb58531e33eafb64215692d81ee4db
Author: george <george@wens.org.uk>
Date:   Sun Dec 3 22:54:20 2023 +0000

    days 1-3

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..664d537
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+target/
+*input
+*.log
diff --git a/day01/Cargo.lock b/day01/Cargo.lock
new file mode 100644
index 0000000..c34d77d
--- /dev/null
+++ b/day01/Cargo.lock
@@ -0,0 +1,54 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "aho-corasick"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2969dcb958b36655471fc61f7e416fa76033bdd4bfed0678d8fee1e2d07a1f0"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "day01"
+version = "0.1.0"
+dependencies = [
+ "regex",
+]
+
+[[package]]
+name = "memchr"
+version = "2.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f665ee40bc4a3c5590afb1e9677db74a508659dfd71e126420da8274909a0167"
+
+[[package]]
+name = "regex"
+version = "1.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "380b951a9c5e80ddfd6136919eef32310721aa4aacd4889a8d39124b026ab343"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5f804c7828047e88b2d32e2d7fe5a105da8ee3264f01902f796c8e067dc2483f"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
diff --git a/day01/Cargo.toml b/day01/Cargo.toml
new file mode 100644
index 0000000..5ec630b
--- /dev/null
+++ b/day01/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "day01"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+regex = "1.10.2"
diff --git a/day01/src/main.rs b/day01/src/main.rs
new file mode 100644
index 0000000..289e1bc
--- /dev/null
+++ b/day01/src/main.rs
@@ -0,0 +1,45 @@
+use std::io::{stdin, BufRead};
+
+const NUM_TEST: [(&str, &str); 9] = [
+    ("one", "1"),
+    ("two", "2"),
+    ("three", "3"),
+    ("four", "4"),
+    ("five", "5"),
+    ("six", "6"),
+    ("seven", "7"),
+    ("eight", "8"),
+    ("nine", "9"),
+];
+
+fn main() {
+    let input = stdin().lock().lines().map(|l| l.unwrap());
+    let mut part_one_total = 0;
+    let mut part_two_total = 0;
+
+    for line in input {
+        part_one_total += part_one_calc(&line);
+        part_two_total += part_two_calc(&line);
+    }
+
+    println!("P1: {} P2: {}", part_one_total, part_two_total);
+}
+
+fn part_two_calc(line: &str) -> usize {
+    let mut line = String::from(line);
+
+    for str in NUM_TEST {
+        if line.contains(str.0) {
+            let swap = str.0.to_string() + str.1 + str.0;
+            line = line.replace(str.0, &swap);
+        }
+    }
+    part_one_calc(&line)
+}
+
+fn part_one_calc(line: &str) -> usize {
+    let mut nums = line.chars().filter(|c| c.is_numeric());
+    let first = nums.next().unwrap_or('0');
+    let last = nums.last().unwrap_or(first);
+    format!("{}{}", first, last).parse().unwrap()
+}
diff --git a/day02/Cargo.lock b/day02/Cargo.lock
new file mode 100644
index 0000000..91d6451
--- /dev/null
+++ b/day02/Cargo.lock
@@ -0,0 +1,54 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "aho-corasick"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2969dcb958b36655471fc61f7e416fa76033bdd4bfed0678d8fee1e2d07a1f0"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "day02"
+version = "0.1.0"
+dependencies = [
+ "regex",
+]
+
+[[package]]
+name = "memchr"
+version = "2.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f665ee40bc4a3c5590afb1e9677db74a508659dfd71e126420da8274909a0167"
+
+[[package]]
+name = "regex"
+version = "1.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "380b951a9c5e80ddfd6136919eef32310721aa4aacd4889a8d39124b026ab343"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5f804c7828047e88b2d32e2d7fe5a105da8ee3264f01902f796c8e067dc2483f"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
diff --git a/day02/Cargo.toml b/day02/Cargo.toml
new file mode 100644
index 0000000..c6376df
--- /dev/null
+++ b/day02/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "day02"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+regex = "1.10.2"
diff --git a/day02/src/main.rs b/day02/src/main.rs
new file mode 100644
index 0000000..5150f94
--- /dev/null
+++ b/day02/src/main.rs
@@ -0,0 +1,61 @@
+use regex::Regex;
+use std::io::{stdin, BufRead};
+
+type Rgb = (usize, usize, usize);
+const THRESHOLD: Rgb = (12, 13, 14);
+
+fn main() {
+    let re = Regex::new(r"\d+ (b|r|g)").unwrap();
+    let input = stdin().lock().lines().map(|l| l.unwrap());
+    let mut id_sum = 0;
+    let mut water_sum = 0;
+
+    for (i, line) in input.enumerate() {
+        let mut possible = true;
+
+        let mut max_rgb = (0, 0, 0);
+        for line_sect in line.split(';') {
+            let mut rgb = (0, 0, 0);
+
+            let games = re
+                .find_iter(line_sect)
+                .map(|l| {
+                    let temp = l.as_str().split_once(' ').unwrap();
+                    (temp.0.parse::<usize>().unwrap(), temp.1)
+                })
+                .collect::<Vec<_>>();
+
+            for game in games.iter() {
+                match game.1 {
+                    "r" => rgb.0 = game.0,
+                    "g" => rgb.1 = game.0,
+                    "b" => rgb.2 = game.0,
+                    _ => (),
+                }
+                if rgb.0 > max_rgb.0 {
+                    max_rgb.0 = rgb.0;
+                }
+
+                if rgb.1 > max_rgb.1 {
+                    max_rgb.1 = rgb.1;
+                }
+
+                if rgb.2 > max_rgb.2 {
+                    max_rgb.2 = rgb.2;
+                }
+
+                if possible && rgb.0 > THRESHOLD.0 || rgb.1 > THRESHOLD.1 || rgb.2 > THRESHOLD.2 {
+                    possible = false;
+                }
+            }
+        }
+
+        let pow = max_rgb.0 * max_rgb.1 * max_rgb.2;
+        water_sum += pow;
+
+        if possible {
+            id_sum += i + 1;
+        }
+    }
+    println!("P1: {}, P2: {}", id_sum, water_sum);
+}
diff --git a/day03/Cargo.lock b/day03/Cargo.lock
new file mode 100644
index 0000000..21c74cb
--- /dev/null
+++ b/day03/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day03"
+version = "0.1.0"
diff --git a/day03/Cargo.toml b/day03/Cargo.toml
new file mode 100644
index 0000000..2804bab
--- /dev/null
+++ b/day03/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "day03"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/day03/src/main.rs b/day03/src/main.rs
new file mode 100644
index 0000000..101c1c1
--- /dev/null
+++ b/day03/src/main.rs
@@ -0,0 +1,114 @@
+use std::collections::HashMap;
+use std::io::{stdin, BufRead};
+
+type Point = (usize, usize);
+const EMPTY_SYMBOL: char = '.';
+const GEAR_SYMBOL: char = '*';
+const DEFAULT_POINT: Point = (usize::MAX, usize::MAX);
+
+fn main() {
+    let input = stdin()
+        .lock()
+        .lines()
+        .map(|l| l.unwrap().chars().collect::<Vec<_>>())
+        .collect::<Vec<_>>();
+
+    let mut sum = 0;
+    let mut gear_surrounding_nums: HashMap<Point, Vec<usize>> = HashMap::new();
+
+    for (y, row) in input.iter().enumerate() {
+        let mut current_num = String::new();
+        let mut valid = false;
+        let mut gear_pos = DEFAULT_POINT;
+
+        for (x, col) in row.iter().enumerate() {
+            if col.is_ascii_digit() {
+                current_num.push(*col);
+                let points = points_around(x, y);
+
+                for point in points {
+                    if let Some(adjacent_symbol) = get_at_point(point.0, point.1, &input) {
+                        if !adjacent_symbol.is_ascii_digit() && adjacent_symbol != &EMPTY_SYMBOL {
+                            valid = true;
+                        }
+                        if adjacent_symbol == &GEAR_SYMBOL {
+                            gear_pos = point;
+                        }
+                    }
+                }
+            } else if !current_num.is_empty() {
+                check_and_update_point(
+                    valid,
+                    &current_num,
+                    &mut sum,
+                    &gear_pos,
+                    &mut gear_surrounding_nums,
+                );
+                gear_pos = DEFAULT_POINT;
+                valid = false;
+                current_num.clear();
+            }
+        }
+        check_and_update_point(
+            valid,
+            &current_num,
+            &mut sum,
+            &gear_pos,
+            &mut gear_surrounding_nums,
+        );
+    }
+
+    let part2 = gear_surrounding_nums
+        .iter()
+        .filter_map(|gear| match gear.1.len() == 2 {
+            true => Some(gear.1),
+            _ => None,
+        })
+        .fold(0, |total, gear_vals| {
+            total + gear_vals.iter().product::<usize>()
+        });
+
+    println!("P1: {} P2: {}", sum, part2);
+}
+
+fn check_and_update_point(
+    valid: bool,
+    current_num: &str,
+    sum: &mut usize,
+    gear_pos: &Point,
+    gear_surrounding_nums: &mut HashMap<Point, Vec<usize>>,
+) {
+    if valid {
+        let numeric_val = current_num.parse::<usize>().unwrap();
+
+        *sum += numeric_val;
+        if *gear_pos != DEFAULT_POINT {
+            let gears = gear_surrounding_nums.get_mut(gear_pos);
+            if let Some(gear_vec) = gears {
+                gear_vec.push(numeric_val);
+            } else {
+                gear_surrounding_nums.insert(*gear_pos, vec![numeric_val]);
+            }
+        }
+    }
+}
+
+fn get_at_point(x: usize, y: usize, grid: &[Vec<char>]) -> Option<&char> {
+    if let Some(row) = grid.get(y) {
+        return row.get(x);
+    }
+    None
+}
+
+fn points_around(x: usize, y: usize) -> Vec<Point> {
+    let mut points = Vec::new();
+    for i in x.saturating_sub(1)..(x + 2) {
+        for j in y.saturating_sub(1)..(y + 2) {
+            if (i, j) == (x, y) {
+                continue;
+            }
+            points.push((i, j));
+        }
+    }
+    points
+}