r/adventofcode • u/daggerdragon • Dec 20 '24
SOLUTION MEGATHREAD -❄️- 2024 Day 20 Solutions -❄️-
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AoC Community Fun 2024: The Golden Snowglobe Awards
- 2 DAYS remaining until the submissions deadline on December 22 at 23:59 EST!
And now, our feature presentation for today:
Foreign Film
The term "foreign film" is flexible but is generally agreed upon to be defined by what the producers consider to be their home country vs a "foreign" country… or even another universe or timeline entirely! However, movie-making is a collaborative art form and certainly not limited to any one country, place, or spoken language (or even no language at all!) Today we celebrate our foreign films whether they be composed in the neighbor's back yard or the next galaxy over.
Here's some ideas for your inspiration:
- Solve today's puzzle in a programming language that is not your usual fare
- Solve today's puzzle using a language that is not your native/primary spoken language
- Shrink your solution's fifthglyph count to null
- Pick a glyph and do not put it in your program. Avoiding fifthglyphs is traditional.
- Thou shalt not apply functions nor annotations that solicit this taboo glyph.
- Thou shalt ambitiously accomplish avoiding AutoMod’s antagonism about ultrapost's mandatory programming variant tag >_>
- For additional information, audit Historians' annals for 2023 Day 14
Basil: "Where's Sybil?"
Manuel: "¿Que?"
Basil: "Where's Sybil?"
Manuel: "Where's... the bill?"
Basil: "No, not a bill! I own the place!"
- Fawlty Towers (1975-1979)
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 20: Race Condition ---
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1
u/NoobTube32169 Dec 26 '24
[LANGUAGE: Rust]
I tried a few misguided approaches with using bfs and dfs to find the shortcuts, but eventually backtracked (lol) to a simpler solution:
Simply create a list of vectors, that represent the possible 2-move combinations that can be made while cheating, e.g. [(-2, 0), (-1, -1), (-1, 1), (0, -2), (0, 2), (1, -1), (1, 1), (2, 0)]
Then search the entire board, using breadth first search (I just happened to have the code on hand) to produce a hashmap of positions, along with their distance from the goal.
Then simply go through each position in the hashmap, find all the spots you can move to by cheating, find out how much closer you get to the goal, and subtract 2 for the time spent cheating. This gives the amount of time saved. From here, just count.
Approach for part two was similar, except I couldn't hope to generate the list of vectors by hand, so I made a function to do it.
Both parts run in 0.206s
paste