day11 part2 done

2022-aoc/src/d11.rs

@@ -24,10 +24,10 @@ impl Default for Operation {
 }
 
 impl Monkey {
-    pub fn inspect(&mut self) -> Vec<(usize, u128)> {
+    pub fn inspect(&mut self, reducer: &dyn Fn(u128) -> u128) -> Vec<(usize, u128)> {
         let mut out = Vec::with_capacity(self.items.len());
         while let Some(item) = self.items.pop_front() {
-            let item = self.op(item) / 3;
+            let item = reducer(self.op(item));
             if item % self.tmod == 0 {
                 out.push((self.target.0, item));
             } else {
@@ -115,7 +115,7 @@ fn part1(troop: &[Monkey]) -> u128 {
     for _round in 0..20 {
         for i in 0..troop.len() {
             let monkey = &mut troop[i];
-            let items = monkey.inspect();
+            let items = monkey.inspect(&|item| item / 3);
             for (target, item) in items {
                 let m = &mut troop[target];
                 m.items.push_back(item);
@@ -128,7 +128,20 @@ fn part1(troop: &[Monkey]) -> u128 {
 
 #[aoc_run(day11, part2)]
 fn part2(troop: &[Monkey]) -> u128 {
-    0
+    let max: u128 = troop.iter().map(|m| m.tmod).product();
+    let mut troop = troop.to_owned();
+    for _round in 0..10_000 {
+        for i in 0..troop.len() {
+            let monkey = &mut troop[i];
+            let items = monkey.inspect(&|item| item % max);
+            for (target, item) in items {
+                let m = &mut troop[target];
+                m.items.push_back(item);
+            }
+        }
+    }
+    troop.sort_by(|m1, m2| m2.business.cmp(&m1.business));
+    troop.iter().take(2).map(|m| m.business).product()
 }
 
 #[cfg(test)]
@@ -172,129 +185,6 @@ Monkey 3:
     #[test]
     fn part2_test() {
         let v = parse_input(INPUT);
-        assert_eq!(part2(&v), 1);
+        assert_eq!(part2(&v), 2713310158);
-    }
-
-    #[test]
-    fn leah_test() {
-        let troop = parse_input(
-            "Monkey 0:
-  Starting items: 54, 82, 90, 88, 86, 54
-  Operation: new = old * 7
-  Test: divisible by 11
-    If true: throw to monkey 2
-    If false: throw to monkey 6
-
-Monkey 1:
-  Starting items: 91, 65
-  Operation: new = old * 13
-  Test: divisible by 5
-    If true: throw to monkey 7
-    If false: throw to monkey 4
-
-Monkey 2:
-  Starting items: 62, 54, 57, 92, 83, 63, 63
-  Operation: new = old + 1
-  Test: divisible by 7
-    If true: throw to monkey 1
-    If false: throw to monkey 7
-
-Monkey 3:
-  Starting items: 67, 72, 68
-  Operation: new = old * old
-  Test: divisible by 2
-    If true: throw to monkey 0
-    If false: throw to monkey 6
-
-Monkey 4:
-  Starting items: 68, 89, 90, 86, 84, 57, 72, 84
-  Operation: new = old + 7
-  Test: divisible by 17
-    If true: throw to monkey 3
-    If false: throw to monkey 5
-
-Monkey 5:
-  Starting items: 79, 83, 64, 58
-  Operation: new = old + 6
-  Test: divisible by 13
-    If true: throw to monkey 3
-    If false: throw to monkey 0
-
-Monkey 6:
-  Starting items: 96, 72, 89, 70, 88
-  Operation: new = old + 4
-  Test: divisible by 3
-    If true: throw to monkey 1
-    If false: throw to monkey 2
-
-Monkey 7:
-  Starting items: 79
-  Operation: new = old + 8
-  Test: divisible by 19
-    If true: throw to monkey 4
-    If false: throw to monkey 5",
-        );
-        assert_eq!(part1(&troop), 78960);
-    }
-
-    #[test]
-    fn rippy_part1() {
-        let input = "Monkey 0:
-  Starting items: 96, 60, 68, 91, 83, 57, 85
-  Operation: new = old * 2
-  Test: divisible by 17
-    If true: throw to monkey 2
-    If false: throw to monkey 5
-
-Monkey 1:
-  Starting items: 75, 78, 68, 81, 73, 99
-  Operation: new = old + 3
-  Test: divisible by 13
-    If true: throw to monkey 7
-    If false: throw to monkey 4
-
-Monkey 2:
-  Starting items: 69, 86, 67, 55, 96, 69, 94, 85
-  Operation: new = old + 6
-  Test: divisible by 19
-    If true: throw to monkey 6
-    If false: throw to monkey 5
-
-Monkey 3:
-  Starting items: 88, 75, 74, 98, 80
-  Operation: new = old + 5
-  Test: divisible by 7
-    If true: throw to monkey 7
-    If false: throw to monkey 1
-
-Monkey 4:
-  Starting items: 82
-  Operation: new = old + 8
-  Test: divisible by 11
-    If true: throw to monkey 0
-    If false: throw to monkey 2
-
-Monkey 5:
-  Starting items: 72, 92, 92
-  Operation: new = old * 5
-  Test: divisible by 3
-    If true: throw to monkey 6
-    If false: throw to monkey 3
-
-Monkey 6:
-  Starting items: 74, 61
-  Operation: new = old * old
-  Test: divisible by 2
-    If true: throw to monkey 3
-    If false: throw to monkey 1
-
-Monkey 7:
-  Starting items: 76, 86, 83, 55
-  Operation: new = old + 4
-  Test: divisible by 5
-    If true: throw to monkey 4
-    If false: throw to monkey 0";
-        let troop = parse_input(input);
-        assert_eq!(part1(&troop), 56595);
     }
 }