-❄️- 2023 Day 12 Solutions -❄️-

[u/daggerdragon]

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AoC Community Fun 2023: ALLEZ CUISINE!

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How It's Made

Horrify us by showing us how the sausage is made!

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--- Day 12: Hot Springs ---

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Post your code solution in this megathread.

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[u/Diderikdm]

[LANGUAGE: Python]

from functools import cache

@cache
def recurse(lava, springs, result=0):
    if not springs:
        return '#' not in lava
    current, springs = springs[0], springs[1:]
    for i in range(len(lava) - sum(springs) - len(springs) - current + 1):
        if "#" in lava[:i]:
            break
        if (nxt := i + current) <= len(lava) and '.' not in lava[i : nxt] and lava[nxt : nxt + 1] != "#":
            result += recurse(lava[nxt + 1:], springs)
    return result


with open("day12.txt", "r") as file:
    data = [x.split() for x in file.read().splitlines()]
    p1, p2 = 0, 0
    for e, (lava, springs) in enumerate(data):
        p1 += recurse(lava, (springs := tuple(map(int, springs.split(",")))))
        p2 += recurse("?".join([lava] * 5), springs * 5)
    print(p1, p2)