2023 Day 14: Parabolic Reflector Dish

:satellite: Fake spoiler: it didn’t require the use of the quadratic formula.

Not too difficult; I had more trouble with part 1 than with part 2. For part 2, it seemsto suffice to run at most 1,000 spin cycles, then determine the period in the loads after every spin cycle, which isn’t hard to do automatically. My period was 7.

A possible trap I fell into is to detect possible cycles that may occur after each step (North, West, South, East).
Another possible trap (I didn’t fell into) could be to hash the whole stone map. Actually what you care about is the “total load”, that’s it!
A little disappointment in the puzzle (part 2) is that the character is only interested by the 1_000_000_000th load and not the maximum load over that amount of cycles.

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I thought of that first trap, only because I fell into it when doing an earlier puzzle.

For the second, yeah, hashing the entire stone map would probably kill you.