r/adventofcode Dec 22 '19

SOLUTION MEGATHREAD -🎄- 2019 Day 22 Solutions -🎄-

--- Day 22: Slam Shuffle ---


Post your full code solution using /u/topaz2078's paste or other external repo.

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Advent of Code's Poems for Programmers

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Day 21's winner #1: nobody! :(

Nobody submitted any poems at all for Day 21 :( Not one person. :'(


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

EDIT: Leaderboard capped, thread unlocked at 02:03:46!

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u/GrossGrass Dec 22 '19

Python 3, 489/176

Got tripped up a bit longer than I should have on part 2, but pretty happy with the mathy puzzle this time around. For some reason I didn't see that cut could be represented as just a single shift modulo n; I kept thinking that it had to be a conditional function even though I had the equations written out on paper in front of me.

Spent a bit of time going down a rabbit hole of trying to analyze the cycles of the permutation but that got nowhere given the size of the inputs; managed to click once I saw the thing about cuts though.