Day 24 part 1.

src/tasks/day24.rs

@@ -8,8 +8,6 @@ pub fn task1() {
 
     let remaining_units = play(&input);
     println!("Standing units after the game: {}", remaining_units);
-    // 21107 too high
-    // 21004 too high
 }
 
 fn play(input: &str) -> i64 {
@@ -38,10 +36,7 @@ fn play(input: &str) -> i64 {
         rounds_played += 1;
     }
 
-    println!("{:#?}", game);
-    println!("Played {} rounds", rounds_played);
-
-    game.groups.values().map(|it| it.units).sum::<i64>()
+    game.remaining_units()
 }
 
 #[derive(Debug)]
@@ -50,6 +45,10 @@ struct Game {
 }
 
 impl Game {
+    fn remaining_units(&self) -> i64 {
+        self.groups.values().map(|it| it.units).sum::<i64>()
+    }
+
     fn create(input: &str) -> Self {
         let mut groups = HashMap::new();
         let mut team = Team::ImmuneSystem;
@@ -65,6 +64,8 @@ impl Game {
                 group => {
                     if let Some(group) = Group::from_str(group, team, id) {
                         groups.insert(id, group);
+                    } else {
+                        panic!("bad group: {group}");
                     }
                 }
             }
@@ -77,22 +78,21 @@ impl Game {
         // lock targets ordered by effective power
         let mut all_by_power: Vec<&Group> = self.groups.values().collect();
         all_by_power.sort_unstable_by_key(|a| Reverse((a.effective_power(), a.initiative)));
-        for group in all_by_power.iter() {
-            println!(
-                "{}: {} ({})",
-                group.id,
-                group.effective_power(),
-                group.initiative
-            );
-        }
-        println!("{:?}", all_by_power);
+        // for group in all_by_power.iter() {
+        //     println!(
+        //         "{}: {} ({})",
+        //         group.id,
+        //         group.effective_power(),
+        //         group.initiative
+        //     );
+        // }
+        // println!("{:?}", all_by_power);
         for group in all_by_power.iter() {
             if let Some(t) = self
                 .groups
                 .values()
                 .filter(|it| it.team != group.team)
                 .filter(|it| !target.values().any(|t| *t == it.id))
-                // .filter(|it| group.compute_attack_damage_to(&it) >= it.hp_each)
                 // .inspect(|it| {
                 //     println!(
                 //         "{} would deal {} damage to {}",
@@ -110,10 +110,10 @@ impl Game {
                 })
             {
                 if group.compute_attack_damage_to(t) <= 0 {
-                    println!(
-                        "Didn't find a target where {:?} can deal positive damage.",
-                        group
-                    );
+                    // println!(
+                    //     "Didn't find a target where {:?} can deal positive damage.",
+                    //     group
+                    // );
                     continue;
                 } else {
                     target.insert(group.id, t.id);
@@ -128,20 +128,19 @@ impl Game {
         for active_id in all_ids_by_initiative {
             if !self.groups[&active_id].alive() {
                 // was killed in this round
-                println!("Group {} already dead", active_id);
+                // println!("Group {} already dead", active_id);
                 continue;
             }
             if let Some(enemy_id) = target.get(&active_id) {
                 let enemy = &self.groups[enemy_id];
                 let damage: i64 = self.groups[&active_id].compute_attack_damage_to(enemy);
                 let dying_units = damage / enemy.hp_each;
-                if let Some(enemy) = self.groups.get_mut(enemy_id) {
-                    enemy.units -= dying_units;
-                }
-                println!(
-                    "{} dealt {} ({} units) damage to {}",
-                    active_id, damage, dying_units, enemy_id
-                );
+                self.groups.get_mut(enemy_id).unwrap().units -= dying_units;
+
+                // println!(
+                //     "{} dealt {} ({} units) damage to {}",
+                //     active_id, damage, dying_units, enemy_id
+                // );
             }
         }
 
@@ -151,8 +150,7 @@ impl Game {
     }
 
     fn is_over(&self) -> bool {
-        self.groups.is_empty()
-            || self.groups.iter().all(|(_, it)| it.team == Team::Infection)
+        self.groups.iter().all(|(_, it)| it.team == Team::Infection)
             || self
                 .groups
                 .iter()
@@ -182,8 +180,9 @@ struct Group {
 impl Group {
     fn from_str(input: &str, team: Team, id: usize) -> Option<Self> {
         // 801 units each with 4706 hit points (weak to radiation) with an attack that does 116 bludgeoning damage at initiative 1
+        // 2347 units each with 3322 hit points with an attack that does 12 cold damage at initiative 2
         use regex::Regex;
-        let regex = Regex::new(r"(\d+) units each with (\d+) hit points \((.+)\) with an attack that does (\d+) (\w+) damage at initiative (\d+)").unwrap();
+        let regex = Regex::new(r"(\d+) units each with (\d+) hit points(.*)with an attack that does (\d+) (\w+) damage at initiative (\d+)").unwrap();
         if let Some(m) = regex.captures(input) {
             let units: i64 = m[1].parse().unwrap();
             let hp_each: i64 = m[2].parse().unwrap();
@@ -192,7 +191,8 @@ impl Group {
             let initiative: u64 = m[6].parse().unwrap();
             let mut weaknesses: Vec<String> = Vec::new();
             let mut immunities: Vec<String> = Vec::new();
-            for part in m[3].split("; ") {
+            let attributes = m[3].trim().trim_start_matches("(").trim_end_matches(")");
+            for part in attributes.split("; ") {
                 if let Some(stripped) = part.strip_prefix("weak to ") {
                     weaknesses = stripped.split(", ").map(|it| it.to_string()).collect();
                 } else if let Some(stripped) = part.strip_prefix("immune to ") {