I’d like to see your solution in total. I’m not too familiar with the nuts and bolts, but hash set is quite a bit more expensive than a simple vector, there’s a bunch of overhead incurred when executing the hashing and placing of the data, and when repeating a few thousand times it sure adds up. My part one hovers around 600 microseconds.

Not who you asked but: I save coordinates and direction into a vector each time the guard faces a #. Also every time the guard faces a #, I check if the position exists in the vector, if true, it’s an infinite loop. 78ms rust aolution.

Rust

This one was the first real think for this year, but I ended up brute forcing it, placing a ‘#’ in every position and checking. part 2 runs in about 380ms 78ms (after reducing the amount ‘#’-placements to only where the guard walks) on my 2011 core i-7, so I’m happy, even though it feels like I could have been smarter.

Part 1 Part 2

Still in rust, and still inexperienced.

Forgot to make a separate solve for part two, for part one, imagine this without the make_valid function and some slightly different structure changes around the accumulator in babbage().

Used a hash map to track what should be in order, and a few indexed loops to keep track of where I’m at and where to look forward.

Day 5

This looks so alien! Does it work with the full set? The comment says 5, choose 4, but I guess it’s written as n, choose n-1?

This is my very naive rust solution, part 2 is mostly just an extra function, so they’re bother covered in this one.

AoC day 2

I’m quite inexperienced as a programmer, I learned most of the basic concepts from playing human resource machine and 7 billion humans. After mucking about writing some CLI utilities in Perl and python, I’ve decided to give rust a go.

Part 1

Part 2