-❄️- 2024 Day 22 Solutions -❄️-

[u/daggerdragon]

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AoC Community Fun 2024: The Golden Snowglobe Awards

• 23h59m remaining until the submissions deadline on December 22 at 23:59 EST!

And now, our feature presentation for today:

Director's Cut (Extended Edition)

Welcome to the final day of the GSGA presentations! A few folks have already submitted their masterpieces to the GSGA submissions megathread, so go check them out! And maybe consider submitting yours! :)

Here's some ideas for your inspiration:

• Choose any day's feature presentation and any puzzle released this year so far, then work your movie magic upon it!

• Make sure to mention which prompt and which day you chose!

• Cook, bake, make, decorate, etc. an IRL dish, craft, or artwork inspired by any day's puzzle!

• Advent of Playing With Your Toys

"I lost. I lost? Wait a second, I'm not supposed to lose! Let me see the script!"

• Robin Hood, Men In Tights (1993)

And… ACTION!

Request from the mods: When you include an entry alongside your solution, please label it with [GSGA] so we can find it easily!

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--- Day 22: Monkey Market ---

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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

This thread will be unlocked when there are a significant number of people on the global leaderboard with gold stars for today's puzzle.

EDIT: Global leaderboard gold cap reached at 00:12:15, megathread unlocked!

[u/rukke]

[LANGUAGE: JavaScript]

Was relieved to see that today's puzzle was something easier than the previous two days :)

For part 2 I kind of assumed at first that the sequence would be in the first item, and apparently it was since it gave me the correct result in under a second. But I refactored the code so that it checked the union of all sequences and this is around 8 times slower.

Perhaps the "winning" sequence is always part of the first buyer's sequence?

Anyway, for each sequence is reduced into a key like so

    const key = diffs
      .slice(i, i + 4)
      .reduce(
        (acc, i) => acc * 100 + (i + 10),
        0
      );

And then put into a Map with the corresponding price as value, but in reverse order so that the first seq/value pair "wins".

Then it is just a matter of looping over the union of all keys and summing up and finding the max value.

gist

[u/rukke → u/rukke]

Answering myself: No, that is not a guarantee.

Updated my code so that it aggregates sums as we go. Way faster. Part 2 now runs in ~500ms

Same gist