Day 10: Factory

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Keep top level comments as only solutions, if you want to say something other than a solution put it in a new post. (replies to comments can be whatever)
You can send code in code blocks by using three backticks, the code, and then three backticks or use something such as https://topaz.github.io/paste/ if you prefer sending it through a URL

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[-] EnEnCode@programming.dev 2 points 1 month ago* (last edited 1 month ago)

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

(/relieving)

I would never have solved this if it weren't for AoC being only 12 days. I don't know if that was a good thing with how much this took out of me.

Written in the Really Ultimate Simplex Tableau (Rust) programming language
Over 600 lines (so long it didn't fit without using paste)
Two-phase simplex fully implemented, refactored to handle inequalities as well as equalities (you need inequalities during branch-and-cut)
Custom Fraction struct because floating-point made me sad (just like every other time I try to use it)
The hackiest branch-and-cut implementation ever (really, you had to add inputs with non-integer optima just to make life harder?)
Hideously unreadable use of iterators
Probably still filled with lingering bugs
All of the comments telling the story of my deteriorating mental state intact
Part 1 included as a bonus
Somehow, actually reasonably performant (37.1 +/- 0.3 ms)

Solution

[-] CameronDev@programming.dev 1 points 1 month ago

I dunno how topaz is meant to work, but I get an error about failing to decompress data on mobile Firefox, is the link right?

[-] EnEnCode@programming.dev 2 points 1 month ago

Lemmy uses %20 in the URL for every '+' character and paste doesn't account for that. I think if you copy-replace all of that, it should work.

[-] CameronDev@programming.dev 1 points 1 month ago

Ah, bit hard to do on mobile, but good to know.

this post was submitted on 10 Dec 2025

13 points (100.0% liked)

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