day2: [rust] part 2

diff --git a/day2/src/game.rs b/day2/src/game.rs
index 11c427c3cd3b367b94dc3640c3da04034b20b08a..37de463b9a01bbc05527c0115484e4f2efca6291 100644 (file)
--- a/day2/src/game.rs
+++ b/day2/src/game.rs
@@ -1,5 +1,6 @@
 use std::str::FromStr;
 use round::Round;
+use std::cmp;
 
 #[derive(Debug, PartialEq, Eq)]
 pub struct Game {
@@ -10,6 +11,18 @@ pub struct Game {
 #[derive(Debug, PartialEq, Eq)]
 pub struct ParseGameError;
 
+impl Game {
+    pub fn power(&self) -> u32 {
+        let mut res = Round {red: 0, green: 0, blue: 0 }; 
+        for round in self.rounds.iter() {
+            res.red = cmp::max(res.red, round.red);
+            res.green = cmp::max(res.green, round.green);
+            res.blue = cmp::max(res.blue, round.blue);
+        }
+        return res.red * res.green * res.blue;
+    }
+}
+
 impl FromStr for Game {
     type Err = ParseGameError;
 
@@ -57,4 +70,10 @@ mod tests {
         ]});
         assert_eq!(Game::from_str("Game 1: 20 red, 1 green, 2 blue; 2 green\n"), expected);
     }
+
+    #[test]
+    fn test_game_power() {
+        let game = Game::from_str("Game 1: 3 blue, 4 red; 1 red, 2 green, 6 blue; 2 green").unwrap();
+        assert_eq!(game.power(), 48);
+    }
 }

diff --git a/day2/src/main.rs b/day2/src/main.rs
index 0b585a5bbc08af347a59600386396d03fb7dfe79..24f4ce561c17e3afc5d9459035dc7edff7be0499 100644 (file)
--- a/day2/src/main.rs
+++ b/day2/src/main.rs
@@ -42,12 +42,17 @@ fn main() -> Result<(), Box<dyn Error>> {
             .collect::<Vec<_>>();
 
         let limits = Round { red: 12, green: 13, blue: 14 };
-        let sum_ids: u32= games.into_iter()
+        let sum_ids: u32 = games.iter()
             .filter(|g| valid_game(g, &limits))
             // .inspect(|g| print_game(g))
             .map(|g| g.id)
             .sum();
         println!("part 1: {}", sum_ids);
+
+        let sum_power: u32 = games.into_iter()
+            .map(|g| g.power())
+            .sum();
+        println!("part 2: {}", sum_power);
     }
     Ok(())
 }