3 files changed, 182 insertions, 0 deletions

diff --git a/day11/__init__.py b/day11/__init__.py
new file mode 100644
index 0000000..7ed8fbc
--- /dev/null
+++ b/day11/__init__.py
@@ -0,0 +1,100 @@
+# -*- coding: utf-8 -*-
+import dataclasses
+from abc import ABC
+from typing import List, Iterator, Any, Tuple
+
+from aoc import BaseAssignment
+
+
+@dataclasses.dataclass
+class Monkey:
+    items: List[int]
+    operation: List[str]
+    test_divisible: int
+    test_true: int
+    test_false: int
+    worry_divider: int = 1
+
+    inspections: int = 0
+
+    @classmethod
+    def from_input(cls, lines: List[str], worry_divider: int):
+        _, items = lines[1].split(":")
+
+        return cls(
+            items=[int(item) for item in items.split(",")],
+            operation=lines[2].split(" ")[-2:],
+            test_divisible=int(lines[3].split(" ")[-1]),
+            test_true=int(lines[4].split(" ")[-1]),
+            test_false=int(lines[5].split(" ")[-1]),
+            worry_divider=worry_divider,
+        )
+
+    def new_worry_factor(self, item: int, worry_factor=1) -> int:
+        operator, value = self.operation
+        value = item if value == "old" else int(value)
+
+        match operator:
+            case "+":
+                return item + value
+            case "*":
+                return item * value
+
+    def throw_to(self, new_worry_factor: int) -> int:
+        if new_worry_factor % self.test_divisible == 0:
+            return self.test_true
+        return self.test_false
+
+    def inspect_items(self) -> Iterator[Tuple[int, int]]:
+        for item in self.items:
+            self.inspections += 1
+            new_worry_factor = self.new_worry_factor(item) // self.worry_divider
+            yield new_worry_factor, self.throw_to(new_worry_factor)
+
+        self.items = []
+
+
+class Assignment(BaseAssignment, ABC):
+    def parse_monkeys(self, input: Iterator[str], worry_divider: int):
+        monkeys = []
+        monkey = []
+        for line in input:
+            if line == "":
+                monkeys.append(Monkey.from_input(monkey, worry_divider))
+                monkey = []
+                continue
+
+            monkey.append(line)
+
+        if len(monkey) != 0:
+            monkeys.append(Monkey.from_input(monkey, worry_divider))
+
+        return monkeys
+
+    def calculate_monkey_business(
+        self, input: Iterator[str], rounds: int, worry_divider: int = 1
+    ):
+        monkeys = self.parse_monkeys(input, worry_divider)
+
+        for _ in range(rounds):
+            for monkey in monkeys:
+                for item, other_monkey in monkey.inspect_items():
+                    monkeys[other_monkey].items.append(item)
+
+        a, b = sorted([monkey.inspections for monkey in monkeys])[-2:]
+
+        return a * b
+
+
+class AssignmentOne(Assignment):
+    example_result = 10605
+
+    def run(self, input: Iterator) -> Any:
+        return self.calculate_monkey_business(input, 20, 3)
+
+
+class AssignmentTwo(Assignment):
+    example_result = 2713310158
+
+    def run(self, input: Iterator) -> Any:
+        return self.calculate_monkey_business(input, 10000)
diff --git a/day11/example.txt b/day11/example.txt
new file mode 100644
index 0000000..30e09e5
--- /dev/null
+++ b/day11/example.txt
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+Monkey 0:
+  Starting items: 79, 98
+  Operation: new = old * 19
+  Test: divisible by 23
+    If true: throw to monkey 2
+    If false: throw to monkey 3
+
+Monkey 1:
+  Starting items: 54, 65, 75, 74
+  Operation: new = old + 6
+  Test: divisible by 19
+    If true: throw to monkey 2
+    If false: throw to monkey 0
+
+Monkey 2:
+  Starting items: 79, 60, 97
+  Operation: new = old * old
+  Test: divisible by 13
+    If true: throw to monkey 1
+    If false: throw to monkey 3
+
+Monkey 3:
+  Starting items: 74
+  Operation: new = old + 3
+  Test: divisible by 17
+    If true: throw to monkey 0
+    If false: throw to monkey 1
diff --git a/day11/input.txt b/day11/input.txt
new file mode 100644
index 0000000..0dd3bf4
--- /dev/null
+++ b/day11/input.txt
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+Monkey 0:
+  Starting items: 80
+  Operation: new = old * 5
+  Test: divisible by 2
+    If true: throw to monkey 4
+    If false: throw to monkey 3
+
+Monkey 1:
+  Starting items: 75, 83, 74
+  Operation: new = old + 7
+  Test: divisible by 7
+    If true: throw to monkey 5
+    If false: throw to monkey 6
+
+Monkey 2:
+  Starting items: 86, 67, 61, 96, 52, 63, 73
+  Operation: new = old + 5
+  Test: divisible by 3
+    If true: throw to monkey 7
+    If false: throw to monkey 0
+
+Monkey 3:
+  Starting items: 85, 83, 55, 85, 57, 70, 85, 52
+  Operation: new = old + 8
+  Test: divisible by 17
+    If true: throw to monkey 1
+    If false: throw to monkey 5
+
+Monkey 4:
+  Starting items: 67, 75, 91, 72, 89
+  Operation: new = old + 4
+  Test: divisible by 11
+    If true: throw to monkey 3
+    If false: throw to monkey 1
+
+Monkey 5:
+  Starting items: 66, 64, 68, 92, 68, 77
+  Operation: new = old * 2
+  Test: divisible by 19
+    If true: throw to monkey 6
+    If false: throw to monkey 2
+
+Monkey 6:
+  Starting items: 97, 94, 79, 88
+  Operation: new = old * old
+  Test: divisible by 5
+    If true: throw to monkey 2
+    If false: throw to monkey 7
+
+Monkey 7:
+  Starting items: 77, 85
+  Operation: new = old + 6
+  Test: divisible by 13
+    If true: throw to monkey 4
+    If false: throw to monkey 0