Initial commit

1 files changed, 48 insertions, 0 deletions

diff --git a/2020/14/puzzle-2.py b/2020/14/puzzle-2.py
new file mode 100755
index 0000000..45fb6ad
--- /dev/null
+++ b/2020/14/puzzle-2.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+
+
+def bitmask(mask: str, num: int) -> tuple[int, ...]:
+	binary = bin(num)[2:]
+	binary = binary.zfill(36)
+	res = ""
+
+	for i in range(len(binary)):
+		if mask[i] == "0":
+			res += binary[i]
+		else:
+			res += mask[i]
+
+	n = res.count("X")
+	combos = tuple(bin(i)[2:].zfill(n) for i in range(2 << n - 1))
+
+	acc: list[str] = []
+	for combo in combos:
+		temp = res
+		for i in range(n):
+			temp = temp.replace("X", combo[i], 1)
+		acc.append(temp)
+
+	return tuple(int(x, 2) for x in acc)
+
+
+def main() -> None:
+	with open("input", "r") as f:
+		lines = f.read().splitlines()
+
+	mem: dict[str, int] = {}
+	mask = ""
+	for line in lines:
+		line = line.split(" ")
+		if line[0] == "mask":
+			mask = line[2]
+		else:
+			address = line[0][4:-1]
+			addresses = bitmask(mask, int(address))
+			for a in addresses:
+				mem[a] = int(line[2])
+
+	print(sum(mem[val] for val in mem))
+
+
+if __name__ == "__main__":
+	main()