Advent of Code 2025 - Day 03 - Python

# Advent of Code 2025 Day 3
from typing import Callable
from typing import Iterable

Battery = tuple[int, ...]


def parse_data(fp: str) -> list[Battery]:
    with open(fp, "r") as f:
        return [tuple(map(int, line.strip())) for line in f.readlines()]


def find_max_value(battery: Battery, n_nums: int) -> int:
    left_len = len(battery) - n_nums + 1
    left_max = 0
    left_start = 0
    for i, v in enumerate(battery[:left_len]):
        left_start = i if v > left_max else left_start
        left_max = v if v > left_max else left_max
    next_n_nums = n_nums - 1
    if next_n_nums == 0:
        return left_max
    else:
        next_val = find_max_value(battery[left_start + 1 :], next_n_nums)
        return int(str(left_max) + str(next_val))


def find_2_max_values(battery: Battery) -> int:
    """
    >>> assert find_2_max_values(list(map(int, "987654321111111"))) == 98
    >>> assert find_2_max_values(list(map(int, "811111111111119"))) == 89
    >>> assert find_2_max_values(list(map(int, "234234234234278"))) == 78
    >>> assert find_2_max_values(list(map(int, "818181911112111"))) == 92
    """
    return find_max_value(battery, 2)


def find_12_max_values(battery: Battery) -> int:
    """
    >>> assert find_12_max_values(list(map(int, "987654321111111"))) == 987654321111
    >>> assert find_12_max_values(list(map(int, "811111111111119"))) == 811111111119
    >>> assert find_12_max_values(list(map(int, "234234234234278"))) == 434234234278
    >>> assert find_12_max_values(list(map(int, "818181911112111"))) == 888911112111
    """
    return find_max_value(battery, 12)


def compute_total_joltage(
    batteries: Iterable[Battery],
    calc_func: Callable[[Battery], int] = find_2_max_values,
) -> int:
    return sum(calc_func(battery) for battery in batteries)


def part_a():
    """
    >>> fp = "day03a.txt"
    >>> batteries = parse_data(fp)
    >>> assert compute_total_joltage(batteries, find_2_max_values) == 357
    """
    fp = "day03.txt"
    batteries = parse_data(fp)
    total_joltage = compute_total_joltage(batteries)
    print(total_joltage)


def part_b():
    """
    >>> fp = "day03a.txt"
    >>> batteries = parse_data(fp)
    >>> assert compute_total_joltage(batteries, find_12_max_values) == 3121910778619
    """
    fp = "day03.txt"
    batteries = parse_data(fp)
    total_joltage = compute_total_joltage(batteries, find_12_max_values)
    print(total_joltage)


if __name__ == "__main__":
    part_a()
    part_b()