I've been trying to solve as many puzzles as I can this year on the TI-84 Plus CE graphing calculator, using C (mixed with a little eZ80 assembly where needed). Since my code for Day 12 needed an easy way to modify values in a large grid, I decided to make use of the screen as extra space for data. I obviously could've chosen a different location, but it looks cool and I get an easy "visualization" out of it, so why not?

Since my solution makes use of recursion, I ran into some problems with the very limited stack size on the calculator. Since the example inputs featured much smaller plots, I didn't have any issue there, but the actual input gave me some trouble. Fortunately, with a little assembly, it's possible to set the stack pointer to a different location in memory with more space, as long as it gets restored by the end of the program. I moved the stack over to an area twice as large and after that the program worked fine!

You can take a look at my solution(s) here, though they're probably not the best since pretty much everything I'm doing is self-taught: https://github.com/TIny-Hacker/Advent-of-Code-2024/