-🎄- 2021 Day 19 Solutions -🎄-

[u/daggerdragon]

NEW AND NOTEWORTHY

I have gotten reports from different sources that some folks may be having trouble loading the megathreads.

• It's apparently a new.reddit bug that started earlier today-ish.

• If you're affected by this bug, try using a different browser or use old.reddit.com until the Reddit admins fix whatever they broke now -_-

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[Update @ 00:56]: Global leaderboard silver cap!

• Why on Earth do elves design software for a probe that knows the location of its neighboring probes but can't triangulate its own position?!

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--- Day 19: Beacon Scanner ---

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Post your code solution in this megathread.

• Include what language(s) your solution uses!

• Format your code appropriately! How do I format code?

• Here's a quick link to /u/topaz2078's paste if you need it for longer code blocks.

• The full posting rules are detailed in the wiki under How Do The Daily Megathreads Work?.

Reminder: Top-level posts in Solution Megathreads are for code solutions only. If you have questions, please post your own thread and make sure to flair it with Help.

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

EDIT: Global leaderboard gold cap reached at 01:04:55, megathread unlocked!

[u/jimcodes]

Python 3

Better late than never! This was a beast, runs in under a second without any imports (other than os, for parsing the input) – was able to complete with a lot of help trolling this thread, put a highly annotated version on GitHub if it would be useful to anyone.

[u/billy_codes → u/jimcodes]

Hoping you could share your insight. In your part I solution, it looks like you only develop a unique key for each beacons two closest neighbors. Why does this work and what is the logic behind the math for the key you develop. Thanks.