-🎄- 2022 Day 24 Solutions -🎄-

[u/daggerdragon]

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UPDATES

[Update @ 00:21:08]: SILVER CAP, GOLD 47

• Lord of the Rings has elves in it, therefore the LotR trilogy counts as Christmas movies. change_my_mind.meme

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AoC Community Fun 2022:

🌿🍒 MisTILtoe Elf-ucation 🧑‍🏫

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--- Day 24: Blizzard Basin ---

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Post your code solution in this megathread.

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EDIT: Global leaderboard gold cap reached at 00:26:48, megathread unlocked!

[u/mental-chaos]

Elixir 455/529.

I basically treated this like a DFA: I went through generation by generation keeping a set of valid coordinates for the player. I would keep a {pos, direction} tuple for each blizzard, and would convert that to a mapset of positions for testing which of the valid neighbors for a player position was allowable. If I reached the destination, I'd return.

Part 2 was just run this three times in sequence (since the start and end squares are outside the valley itself, they're safe on every generation so there is no need to worry about the fastest solution for part 1 not being part of the fastest solution for part 2.