example.txt

@@ -1,5 +1,7 @@
-Game 1: 3 blue, 4 red; 1 red, 2 green, 6 blue; 2 green
-Game 2: 1 blue, 2 green; 3 green, 4 blue, 1 red; 1 green, 1 blue
-Game 3: 8 green, 6 blue, 20 red; 5 blue, 4 red, 13 green; 5 green, 1 red
-Game 4: 1 green, 3 red, 6 blue; 3 green, 6 red; 3 green, 15 blue, 14 red
-Game 5: 6 red, 1 blue, 3 green; 2 blue, 1 red, 2 green
+two1nine
+eightwothree
+abcone2threexyz
+xtwone3four
+4nineeightseven2
+zoneight234
+7pqrstsixteen

src/main.rs

@@ -1,30 +1,50 @@
 use anyhow::Result;
 use fancy_regex::Regex;
-use std::{collections::HashMap, io::stdin};
+use std::{
+    collections::HashMap,
+    fs::File,
+    io::{BufRead, BufReader},
+};
 
 fn main() -> Result<()> {
-    let game_re = Regex::new(r"Game (\d+): (.+)")?;
-    let cube_re = Regex::new(r"(\d+) (blue|red|green)")?;
+    let input = File::open("input.txt")?;
+    let reader = BufReader::new(input);
+
+    let patterns = Regex::new(
+        r#"on(?=e)|tw(?=o)|thre(?=e)|four|fiv(?=e)|six|seve(?=n)|eigh(?=t)|nin(?=e)|1|2|3|4|5|6|7|8|9"#,
+    )?;
+    let num_values = HashMap::from([
+        ("on", "1"),
+        ("tw", "2"),
+        ("thre", "3"),
+        ("four", "4"),
+        ("fiv", "5"),
+        ("six", "6"),
+        ("seve", "7"),
+        ("eigh", "8"),
+        ("nin", "9"),
+    ]);
 
     let mut sum = 0;
-    for line in stdin().lines() {
+    for line in reader.lines() {
         let line = line?;
-        let c = game_re.captures(&line)?.unwrap();
-        let desc = c.get(2).unwrap().as_str();
+        let mut nums = vec![];
+        for m in patterns.find_iter(&line) {
+            let m = m?;
+            let text = m.as_str();
 
-        let mut max_colors = HashMap::from([("red", 0), ("green", 0), ("blue", 0)]);
-        for round in desc.split(';') {
-            for cube in cube_re.captures_iter(round) {
-                let cube = cube?;
-                let count: i32 = cube.get(1).unwrap().as_str().parse()?;
-                let color = cube.get(2).unwrap().as_str();
+            let v: &str = match num_values.get(text) {
+                Some(digit) => digit,
+                None => text,
+            };
 
-                let n = max_colors.get(&color).unwrap();
-                max_colors.insert(color, i32::max(*n, count));
+            nums.push(v);
         }
-        }
-        let power: i32 = max_colors.values().product();
-        sum += power;
+        let mut value = String::new();
+        value.push_str(nums.first().unwrap());
+        value.push_str(nums.last().unwrap());
+
+        sum += value.parse::<i32>().unwrap();
     }
 
     println!("{sum}");