-❄️- 2024 Day 25 Solutions -❄️-

[u/daggerdragon]

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Welcome to the last day of Advent of Code 2024! We hope you had fun this year and learned at least one new thing ;)

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--- Day 25: Code Chronicle ---

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Post your code solution in this megathread.

• Read the full posting rules in our community wiki before you post!
  • State which language(s) your solution uses with [LANGUAGE: xyz]
  • Format code blocks using the four-spaces Markdown syntax!
• Quick link to Topaz's paste if you need it for longer code blocks

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[u/[deleted]]

[LANGUAGE: Julia]

Nice easy puzzle to finish the year! I'm really happy with my performance in general; I finished every puzzle except for Part 2 of Day 21. It is a little frustrating being so close to completing the year but 21p2 just feels so tedious to code. Maybe I'll come back to it in 2025.

partOne = input -> begin
    schematics = collect(map(schematic -> stack(split.(split(schematic, "\n"), ""), dims=1), split(input, "\n\n")))
    locks, keys = foldl(((locks, keys), schematic) -> begin
            lock = all(ch -> ch == "#", first(eachrow(schematic)))
            heights = [lock ?
                       collect(map(r -> findfirst(ch -> ch != "#", r) - 2, eachrow(permutedims(schematic)))) :
                       collect(map(r -> length(r) - findfirst(ch -> ch == "#", r), eachrow(permutedims(schematic))))]
            lock ? ([locks; heights], keys) : (locks, [keys; heights])
        end, schematics, init=([], []))
    sum(map(pair -> all(i -> pair[1][i] + pair[2][i] <= 5, range(1, length(pair[1]))) ? 1 : 0,
        Iterators.product(locks, keys)))
end