1 files changed, 58 insertions, 0 deletions

diff --git a/day7/__init__.py b/day7/__init__.py
new file mode 100644
index 0000000..375c67a
--- /dev/null
+++ b/day7/__init__.py
@@ -0,0 +1,58 @@
+import re
+from functools import lru_cache
+from typing import Iterator, Any, Generator, Dict
+
+from aoc import BaseAssignment
+
+rule_matcher = re.compile(
+    r'(?P<bag>\w+\ \w+) bags contain (?P<contains>no other bags|(((, )?\d \w+\ \w+ bags?)+))\.')
+contains_matcher = re.compile(r'(?P<count>\d+) (?P<bag>\w+\ \w+) bags?')
+
+
+class Assignment(BaseAssignment):
+    def get_bag_contents(self, contents: str) -> dict:
+        content_dict = {}
+        if contents != 'no other bags':
+            for content in contents.split(', '):
+                count = contains_matcher.match(content).groupdict()
+                content_dict[count['bag']] = int(count['count'])
+
+        return content_dict
+
+    def read_input(self, example=False) -> Dict:
+        self.mapping = {}
+
+        for line in super().read_input(example):
+            match = rule_matcher.match(line)
+            rule = match.groupdict()
+            self.mapping[rule['bag']] = self.get_bag_contents(rule['contains'])
+
+
+class AssignmentOne(Assignment):
+    @lru_cache
+    def contains_shiny_gold_bag(self, bag):
+        if 'shiny gold' in self.mapping[bag]:
+            return True
+
+        return any([
+            self.contains_shiny_gold_bag(containing_bag)
+            for containing_bag in self.mapping[bag].keys()
+        ])
+
+    def run(self, input) -> Any:
+        nr_of_possibilities = 0
+        for bag, contains in self.mapping.items():
+            if self.contains_shiny_gold_bag(bag):
+                nr_of_possibilities += 1
+        return nr_of_possibilities
+
+
+class AssignmentTwo(Assignment):
+    def nr_of_bags_inside(self, bag):
+        return sum([
+            count + (count * self.nr_of_bags_inside(containing_bag))
+            for containing_bag, count in self.mapping[bag].items()
+        ])
+
+    def run(self, input) -> Any:
+        return self.nr_of_bags_inside('shiny gold')