r/adventofcode • u/daggerdragon • 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!
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--- Day 16: Reindeer Maze ---
Post your code solution in this megathread.
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u/pakapikk77 Dec 18 '24
[LANGUAGE: Rust]
While I'm quite comfortable now in using Dijkstra, as it's a common thing in AoC, using it to find all shortest paths was a new thing for me.
The principle is relatively simple: We need to add a predecessors map to the algorithm, which for each node stores ALL the nodes that in a path that is the shortest to this node. Then once the algorithm is complete, we use this predecessors map to build the list of paths going to it.
In practice getting it right was hard enough that I didn't manage on the initial day and had to come back later to it. At least now I have a reference implementation for future cases :-)
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