2023-12-10 16:35:49 +01:00

32 lines
1.0 KiB
Python

# SPDX-License-Identifier: MIT
# Copyright (c) 2023 Akumatic
#
# https://adventofcode.com/2023/day/4
import re
def read_file(filename: str = "input.txt") -> list:
with open(f"{__file__.rstrip('code.py')}{filename}", "r") as f:
return [line.strip().split(": ")[1] for line in f.readlines()]
def get_matches(card: str) -> int:
tmp = card.split(" | ")
winning_nums = [int(x) for x in re.findall(r"\d+", tmp[0])]
card_nums = [int(x) for x in re.findall(r"\d+", tmp[1])]
return len([num for num in winning_nums if num in card_nums])
def part1(cards: list) -> int:
return sum(int(2**(get_matches(card) - 1)) for card in cards)
def part2(cards: list) -> int:
matches = [get_matches(card) for card in cards]
count = [1 for _ in cards]
for i in range(len(matches)):
for j in range(i + 1, i + matches[i] + 1):
count[j] += count[i]
return sum(count)
if __name__ == "__main__":
vals = read_file()
print(f"Part 1: {part1(vals)}")
print(f"Part 2: {part2(vals)}")