advent-of-code/2023/d02/ex2/ex2.py

70 lines
1.5 KiB
Python
Executable file

#!/usr/bin/env python
import math
import sys
from collections import Counter
from enum import StrEnum
class Color(StrEnum):
RED = "red"
GREEN = "green"
BLUE = "blue"
Round = Counter[Color]
Game = list[Round]
# The input is in order without skipping, but just in case...
GameRecord = dict[int, Game]
BAG_CONTENTS = Counter(
{
Color.RED: 12,
Color.GREEN: 13,
Color.BLUE: 14,
}
)
def solve(input: list[str]) -> int:
def parse_round(round: str) -> Round:
values = (value.split(" ") for value in round.split(", "))
return Counter({Color(c): int(n) for n, c in values})
# This does *not* expect the "Game <int>:" bit
def parse_game(game: str) -> Game:
rounds = game.split("; ")
return [parse_round(r) for r in rounds]
def parse_line(line: str) -> tuple[int, Game]:
game_id, rounds = line.split(": ")
return int(game_id.removeprefix("Game ")), parse_game(rounds)
def parse(input: list[str]) -> GameRecord:
parsed = map(parse_line, input)
return {id: game for id, game in parsed}
def min_cubes(game: Game) -> dict[Color, int]:
res = Counter({c: 0 for c in Color})
for r in game:
res |= r
return res
def power(game: Game) -> int:
return math.prod(min_cubes(game).values())
games = parse(input)
return sum(map(power, games.values()))
def main() -> None:
input = sys.stdin.read().splitlines()
print(solve(input))
if __name__ == "__main__":
main()