Day 15 part 2.

src/day15.rs

@@ -58,10 +58,42 @@ fn part1(input: &[Ingredient]) -> i32 {
     scores.into_iter().max().unwrap()
 }
 
-// #[aoc(day15, part2)]
-// fn part2(input: &[Ingredient]) -> String {
-//     todo!()
-// }
+#[aoc(day15, part2)]
+fn part2(input: &[Ingredient]) -> i32 {
+    let mut scores = HashSet::new();
+    for a in 0i32..=100 {
+        for b in 0i32..=(100 - a) {
+            for c in 0i32..=(100 - a - b) {
+                for d in 0i32..=(100 - a - b - c) {
+                    if a + b + c + d != 100 {
+                        continue;
+                    }
+                    if a * input[0].calories + b * input[1].calories + c * input[2].calories + d * input[3].calories != 500 {
+                        continue;
+                    }
+                    let mut capacity = a * input[0].capacity + b * input[1].capacity + c * input[2].capacity + d * input[3].capacity;
+                    let mut durability = a * input[0].durability + b * input[1].durability + c * input[2].durability + d * input[3].durability;
+                    let mut flavor = a * input[0].flavor + b * input[1].flavor + c * input[2].flavor + d * input[3].flavor;
+                    let mut texture = a * input[0].texture + b * input[1].texture + c * input[2].texture + d * input[3].texture;
+                    if capacity < 0 {
+                        capacity = 0;
+                    }
+                    if durability < 0 {
+                        durability = 0;
+                    }
+                    if flavor < 0 {
+                        flavor = 0;
+                    }
+                    if texture < 0 {
+                        texture = 0;
+                    }
+                    scores.insert(capacity * durability * flavor * texture);
+                }
+            }
+        }
+    }
+    scores.into_iter().max().unwrap()
+}
 
 struct Ingredient {
     capacity: i32,
@@ -70,18 +102,3 @@ struct Ingredient {
     texture: i32,
     calories: i32,
 }
-//
-// #[cfg(test)]
-// mod tests {
-//     use super::*;
-//
-//     #[test]
-//     fn part1_example() {
-//         assert_eq!(part1(&parse("<EXAMPLE>")), "<RESULT>");
-//     }
-//
-//     #[test]
-//     fn part2_example() {
-//         assert_eq!(part2(&parse("<EXAMPLE>")), "<RESULT>");
-//     }
-// }