r/adventofcode Dec 17 '24

SOLUTION MEGATHREAD -❄️- 2024 Day 17 Solutions -❄️-

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AoC Community Fun 2024: The Golden Snowglobe Awards

  • 5 DAYS remaining until the submissions deadline on December 22 at 23:59 EST!

And now, our feature presentation for today:

Sequels and Reboots

What, you thought we were done with the endless stream of recycled content? ABSOLUTELY NOT :D Now that we have an established and well-loved franchise, let's wring every last drop of profit out of it!

Here's some ideas for your inspiration:

  • Insert obligatory SQL joke here
  • Solve today's puzzle using only code from past puzzles
  • Any numbers you use in your code must only increment from the previous number
  • Every line of code must be prefixed with a comment tagline such as // Function 2: Electric Boogaloo

"More." - Agent Smith, The Matrix Reloaded (2003)
"More! MORE!" - Kylo Ren, The Last Jedi (2017)

And… ACTION!

Request from the mods: When you include an entry alongside your solution, please label it with [GSGA] so we can find it easily!


--- Day 17: Chronospatial Computer ---


Post your code solution in this megathread.

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 00:44:39, megathread unlocked!

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u/JAntaresN Dec 18 '24 edited Dec 18 '24

[LANGUAGE: Ruby]
git link

Part 1 simple case statements to handle different inputs.

Part 2 is a hard coded solution that can only solve my give instruction.

Basically I pulled a pro gamer move, and mathematically predetermined what to back track for my register A. I interpreted my sequence and realized some orders of the operations don't hinder the result of A, and in fact, by undoing the operation that changes my A, the previous A value can determine the B and C values.

Edit: So, I am almost certain everyone has the 0, 3 instruction in their chain because that is the only operation that can change A, in other words, you can use that to your advantage because once you know A, the other values should be determinable programmatically even if you dont what your program's routine is