1 files changed, 38 insertions, 0 deletions
diff --git a/2020/07/puzzle-1.py b/2020/07/puzzle-1.py
new file mode 100755
index 0000000..da054b8
--- /dev/null
+++ b/2020/07/puzzle-1.py
@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+
+
+bdict: dict[str, list[str]] = {}
+
+# Recursively check if a bag can hold a shiny gold bag
+def holds_bag(innerbags: list[str]) -> bool:
+	if "no other" in innerbags:
+		return False
+	elif "shiny gold" in innerbags:
+		return True
+
+	for subbag in innerbags:
+		if holds_bag(bdict[subbag]):
+			return True
+
+
+def main() -> None:
+	global bdict
+	with open("input", "r") as f:
+		lines = f.readlines()
+
+	for baginfo in lines:
+		data = baginfo.split(" bags contain")
+
+		# { bag_name: [contained_bag_1, containted_bag_2, ...] }
+		bdict[data[0]] = [" ".join(b.split(" ")[-3:][:2]) for b in data[1].split(",")]
+
+	count = 0
+	for bag in bdict:
+		if holds_bag(bdict[bag]):
+			count += 1
+
+	print(count)
+
+
+if __name__ == "__main__":
+	main()