Ah! Second advent sunday ... I guess we were all sleeping / spending time with our loved ones ;-)
I'm not sure I'll have to time to hit every puzzle, some of these are tricky!
Anyway, I decided to do today's in JS. I finished both parts but got 15s runtime on part 1 using Arrays. Part 2 basically said to run Part1 100 times, which sounded like an unpleasant waiting game so I took a different approach. I used a double ended queue, which was way faster because it didn't require resizing arrays. Part 2 took only .7s.
You can test the files in the console like: node day9-2.js
Hope all's good!
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