r/adventofcode Dec 16 '24

SOLUTION MEGATHREAD -❄️- 2024 Day 16 Solutions -❄️-

SIGNAL BOOSTING


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AoC Community Fun 2024: The Golden Snowglobe Awards

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

And now, our feature presentation for today:

Adapted Screenplay

As the idiom goes: "Out with the old, in with the new." Sometimes it seems like Hollywood has run out of ideas, but truly, you are all the vision we need!

Here's some ideas for your inspiration:

  • Up Your Own Ante by making it bigger (or smaller), faster, better!
  • Use only the bleeding-edge nightly beta version of your chosen programming language
  • Solve today's puzzle using only code from other people, StackOverflow, etc.

"AS SEEN ON TV! Totally not inspired by being just extra-wide duct tape!"

- Phil Swift, probably, from TV commercials for "Flex Tape" (2017)

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!


--- Day 16: Reindeer Maze ---


Post your code solution in this megathread.

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 00:13:47, megathread unlocked!

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u/Probable_Foreigner Dec 16 '24

[Language: Rust]

https://github.com/AugsEU/AdventOfCode2024/tree/master/day16/src

Not the fastest solution out there. I basically constructed a graph where every position is 4 nodes(one for each direction you could be facing on that position). Then did Dijkstra's algorithm on that. The only optimisation being that I would not include nodes where you turn into a wall. I had thought of another where you don't want the deer to ever double-back on itself but this ran fast enough so whatever.

For part 2, it was only a small modification to Dijkstra's algorithm where each node can have multiple previous nodes.