Advent Of Code

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An unofficial home for the advent of code community on programming.dev! Other challenges are also welcome!

Advent of Code is an annual Advent calendar of small programming puzzles for a variety of skill sets and skill levels that can be solved in any programming language you like.

Everybody Codes is another collection of programming puzzles with seasonal events.

AoC 2025

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Icon base by Lorc under CC BY 3.0 with modifications to add a gradient

console.log('Hello World')

founded 2 years ago

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Ategon@programming.dev

Sigmatics@lemmy.ca

CameronDev@programming.dev

hades@programming.dev

🧦 - 2025 DAY 11 SOLUTIONS - 🧦 (programming.dev)

submitted 2 weeks ago by CameronDev@programming.dev to c/advent_of_code@programming.dev

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Day 11: Reactor

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What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
Where do I participate?: https://adventofcode.com/
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[–] addie@feddit.uk 1 points 2 weeks ago (1 children)

If you work out a solution to yesterday's part 2 which isn't just "cheat and rely on an external solver library", I will be most impressed.

Programming and mathematics have quite a large overlap and if you want to write tough puzzles it'll be "deep in the woods" for both, but that question is very much on the maths side. And "are you able to pass arguments to Z3?" isn't a very satisfying puzzle for me.

[–] Avicenna@programming.dev 2 points 2 weeks ago

I did linear algebra with sympy over Q to reduce the search space to nullspace x [-N,N] grid (which is generally <=2 dimensional in these inputs and N<50 seems sufficient in most cases) then made easy work of it with vectorization. Similarly for part 2 did linear algebra over F2 but the search grid is also much smaller [0,1] x nullspace