advent-of-code/2023/day4.py
Mikaël Capelle 869cd4477f 2023 day 4.
2023-12-04 19:30:44 +01:00

42 lines
1.0 KiB
Python

import sys
from dataclasses import dataclass
@dataclass(frozen=True)
class Card:
id: int
numbers: list[int]
values: list[int]
lines = sys.stdin.read().splitlines()
cards: list[Card] = []
for line in lines:
id_part, e_part = line.split(":")
numbers_s, values_s = e_part.split("|")
cards.append(
Card(
id=int(id_part.split()[1]),
numbers=[int(v.strip()) for v in numbers_s.strip().split()],
values=[int(v.strip()) for v in values_s.strip().split()],
)
)
winnings = [sum(1 for n in card.values if n in card.numbers) for card in cards]
# part 1
answer_1 = sum(2 ** (winning - 1) for winning in winnings if winning > 0)
print(f"answer 1 is {answer_1}")
# part 2
card2cards = {i: list(range(i + 1, i + w + 1)) for i, w in enumerate(winnings)}
card2values = {i: 0 for i in range(len(cards))}
for i in range(len(cards)):
card2values[i] += 1
for j in card2cards[i]:
card2values[j] += card2values[i]
print(f"answer 2 is {sum(card2values.values())}")