From 3ccc1603262c155fb7462bff58a593c2a81c7a27 Mon Sep 17 00:00:00 2001
From: Pascal Phelipot <pascal@phelipot.me>
Date: Sun, 3 Dec 2023 13:11:32 +0100
Subject: [PATCH] Day 3 completed !

---
 src/day3/mod.rs | 63 +++++++++++++++++++++++++++++++++++++++++++++----
 src/main.rs     |  8 +++----
 2 files changed, 61 insertions(+), 10 deletions(-)

diff --git a/src/day3/mod.rs b/src/day3/mod.rs
index 91687b4..7925145 100644
--- a/src/day3/mod.rs
+++ b/src/day3/mod.rs
@@ -7,7 +7,20 @@ struct Match {
     value: u32,
     line: usize,
     range: Range<usize>,
-    is_valid: bool
+    is_valid: bool,
+    gears: Vec<Point>
+}
+
+#[allow(dead_code)]
+pub enum Part {
+    One, 
+    Two
+}
+
+#[derive(Debug, PartialEq)]
+struct Point {
+    x: u32,
+    y: u32
 }
 
 fn is_symbol(line: &[char], range: Range<usize>) -> bool {
@@ -20,8 +33,21 @@ fn is_symbol(line: &[char], range: Range<usize>) -> bool {
     false
 }
 
+fn find_gears(line: &[char], range: Range<usize>, line_offset: usize) -> Vec<Point> {
+    let mut results: Vec<Point> = Vec::new();
+    let x_offset = range.start;
+
+    for (i, c) in line[range].iter().enumerate() {
+        if *c == '*' {
+            results.push(Point { x: (x_offset + i) as u32, y: line_offset as u32 })
+        }
+    }
+
+    results
+}
+
 #[allow(dead_code)]
-pub fn solve(input: Vec<String>) -> u32 {
+pub fn solve(input: Vec<String>, part: Part) -> u32 {
     let regex = Regex::new(r"\d+").unwrap();
 
         let mut matches: Vec<Match> = Vec::new();
@@ -31,7 +57,7 @@ pub fn solve(input: Vec<String>) -> u32 {
         for (i, line) in input.iter().enumerate() {
             for capture in regex.captures_iter(line) {
                 if let Some(capture) = capture.get(0) {
-                    matches.push(Match { value: capture.as_str().parse::<u32>().unwrap(), line: i, range: capture.range(), is_valid: false });
+                    matches.push(Match { value: capture.as_str().parse::<u32>().unwrap(), line: i, range: capture.range(), is_valid: false, gears: Vec::new() });
                 }
             }
             dataset.push(line.chars().collect());
@@ -47,14 +73,19 @@ pub fn solve(input: Vec<String>) -> u32 {
             if item.line >= 1 {
                 
                 b1 = is_symbol(dataset.get(item.line-1).unwrap(), range.to_owned());
+                item.gears.append(&mut find_gears(dataset.get(item.line-1).unwrap(), range.to_owned(), item.line-1));
+
                 println!("\tChecking line #{} - {}\t'{:?}'", item.line-1, b1, &dataset.get(item.line-1).unwrap()[range.to_owned()]);
             }
             
             let b2 = is_symbol(dataset.get(item.line).unwrap(), range.to_owned());
+            item.gears.append(&mut find_gears(dataset.get(item.line).unwrap(), range.to_owned(), item.line));
             println!("\tChecking line #{} - {}\t'{:?}'", item.line, b2, &dataset.get(item.line).unwrap()[range.to_owned()]);
             
             if item.line < dataset.len() - 1 {
                 b3 = is_symbol(dataset.get(item.line+1).unwrap(), range.to_owned());
+                item.gears.append(&mut find_gears(dataset.get(item.line+1).unwrap(), range.to_owned(), item.line+1));
+                
                 println!("\tChecking line #{} - {}\t'{:?}'", item.line+1, b1, &dataset.get(item.line+1).unwrap()[range.to_owned()]);
             }
 
@@ -68,7 +99,22 @@ pub fn solve(input: Vec<String>) -> u32 {
             }
         }
 
-        sum
+        let mut sum_gears = 0;
+        for (i, item) in matches.iter().enumerate() {
+            for gears_point in &item.gears {
+                for other_match in &matches[(i+1)..] {
+                    if other_match.gears.contains(gears_point) {
+                        println!("Match gear at {:?} -> {} * {}", gears_point, item.value, other_match.value);
+                        sum_gears += item.value * other_match.value;
+                    }
+                }
+            }
+        }
+
+        match part {
+            Part::One => sum,
+            Part::Two => sum_gears
+        }
 }
 
 
@@ -80,6 +126,13 @@ mod tests {
     fn parse() {
         let input: Vec<String> = "467..114..\n...*......\n..35..633.\n......#...\n617*......\n.....+.58.\n..592.....\n......755.\n...$.*....\n.664.598..".lines().map(|v| v.to_owned()).collect();
         
-        assert_eq!(solve(input), 4361);
+        assert_eq!(solve(input, Part::One), 4361);
+    }
+
+    #[test]
+    fn parse_part2() {
+        let input: Vec<String> = "467..114..\n...*......\n..35..633.\n......#...\n617*......\n.....+.58.\n..592.....\n......755.\n...$.*....\n.664.598..".lines().map(|v| v.to_owned()).collect();
+        
+        assert_eq!(solve(input, Part::Two), 467835);
     }
 }
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
index 2ba712a..20b97d9 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -9,10 +9,6 @@ mod utils;
 
 
 fn main() {
-    let data_path = "./datasets/adventofcode.com_2023_day_3_input.txt";
-    let result = day3::solve(utils::lines_from_file(data_path).expect("Could not load the dataset for day 3"));
-
-    println!("result: {}", result);
 }
 
 
@@ -44,8 +40,10 @@ mod tests {
     #[test]
     fn day3() {
         let data_path = "./datasets/adventofcode.com_2023_day_3_input.txt";
-        let result = day3::solve(utils::lines_from_file(data_path).expect("Could not load the dataset for day 3"));
+        let result = day3::solve(utils::lines_from_file(data_path).expect("Could not load the dataset for day 3"), day3::Part::One);
+        let result2 = day3::solve(utils::lines_from_file(data_path).expect("Could not load the dataset for day 3"), day3::Part::Two);
 
         assert_eq!(result, 522726);
+        assert_eq!(result2, 81721933);
     }
 }
\ No newline at end of file