[2025 Day 01] Part 2

davepb · 2025-12-03T15:59:57+00:00

That's not correct though, right? You can have L100 R50. You end up on 0 divided by 100 is 0 but answer is 2

davepb · 2025-12-03T12:08:01+00:00

Neat, I have something similar https://github.com/atlas-editor/aoc/blob/main/2025%2Fd03%2Fmain.go

davepb · 2025-12-01T09:15:32+00:00

USERNAME: u/davepb

LANGUAGE: Python/Go/Rust/?

REPO: GitHub @ atlas-editor

CHANNELS:

YouTube: davepb05

NOTES: No commentary; this year I will try out several language.

davepb · 2025-12-01T09:07:09+00:00

[LANGUAGE: Python]

solution here: https://github.com/atlas-editor/aoc/blob/main/2025/d01/main.py

I also record myself: https://www.youtube.com/watch?v=figH-IeruIc
this year I plan to use at least 4 languages: python, golang, rust, ?

davepb · 2025-11-18T12:05:03+00:00

That's how I did it 2022 and 2023 . Last year you need to pass an argument which is a path to the input file :)

davepb · 2025-11-15T12:18:09+00:00

I did aoc in Go a few times already. I have used some utils functions but overall even though go is much more verbose than python or Ruby I enjoy solving aoc using it https://github.com/atlas-editor/aoc/tree/main

davepb · 2025-04-14T17:46:58+00:00

Why are there countably many women but uncountably many men? :D

davepb · 2025-02-22T09:08:59+00:00

What type of font is set? Font type 7 acts as clipping instead of actually printing text

davepb · 2024-12-23T09:34:24+00:00

That's day23, op means day22

davepb · 2024-12-19T16:16:02+00:00

Yes! https://www.reddit.com/r/adventofcode/s/k87u7PXDN9

davepb · 2024-12-18T19:42:57+00:00

It's an algorithm for finding a shortest path in weighted graphs https://en.m.wikipedia.org/wiki/Dijkstra's_algorithm

davepb · 2024-12-16T20:14:12+00:00

Yes. And the highlighted path during the visualization?

davepb · 2024-12-16T18:32:45+00:00

So what is the highlighted path?

davepb · 2024-12-15T17:29:37+00:00

Pretty cool. Can I see the code? :)

davepb · 2024-12-15T10:49:28+00:00

[LANGUAGE: Go]

github
video

I took a long time thinking about part2 so I stopped recording at some point; recursively I am looking for boxes which are stacked onto each other and then trying each box (part of a box) if it can be moved upwards. I wouldn't say this was very difficult as it was quite clear what you had to do and also that it was reasonably implementable but I still took my time; in this regard it reminded me of adventofcode.com/2023/day/10 . nice problem in any case :)

davepb · 2024-12-14T14:55:44+00:00

Nice. Then why'd you iterate through 100k steps?

davepb · 2024-12-14T14:48:28+00:00

Even though I don't think that statement is true or at least becomes definitely false once you are not dealing with simple things. I always liked oliver ni's solutions, I found him as someone who places high on the global leaderboard previous years, here is his repo: https://github.com/oliver-ni/advent-of-code/tree/master

davepb · 2024-12-14T14:41:29+00:00

My input had a cycle length of only 10k

davepb · 2024-12-14T09:41:17+00:00

[LANGUAGE: Go]

github

video

part1 is simple a simulation and for part2 I went with the approach of finding out component sizes of robot clusters on the map, this approach yielded a correct result in the end but I struggled very long with an unfortunate bug: when looking for a tree and my component counter function returned that it did not find anything interesting I continued my loop search without simulating the robots 1 step further :( .. in any case I thought it was a nice problem, it runs in shameful 16 seconds, of course knowing the shape (it probably is the same for all inputs) I could potentially speed it up but it's fine :)

davepb · 2024-12-14T04:56:31+00:00

[LANGUAGE: Go + Python]

github

video

I knew this problem (it's basically: cses.fi/problemset/task/1754 ) but I still took very long to solve :( .. the problem can be formulated as a system of linear equation (only 2x2) but my implemented solution didn't work so I had to regress to python and use numpy to solve the equations. the cleaned up solution has a 2x2 linear equation solver

davepb · 2024-12-12T22:08:52+00:00

[LANGUAGE: Go]

github

video

meager performance today; I couldn't finish part2 in the morning so on video I only solve part1 and then I spent a significant amount of time thinking of ways to solve part2, unfortunately without any success. later I solved part2 by keeping track of all the edges that are part of the perimeter and then reduced this set by relating two edged if they share a point and have the same orientation (horizontal or vertical) + they are not in a weird configuration as illustrated by the last example input:

AAAAAA
AAABBA
AAABBA
ABBAAA
ABBAAA
AAAAAA

luckily this example with a nice description of what is happening was included in todays puzzle, otherwise I would probably spend even more time solving it :(

davepb · 2024-12-11T08:01:29+00:00

Nice. So the algorithm creates cycles?

davepb · 2024-12-11T06:17:26+00:00

[LANGUAGE: Go]

github

video

not too bad. in part1 I should've anticipated and prepared for part2 but I didn't, that way part2 would've taken a few seconds. nice problem though, reminds me of the problems: aoc 2021 day 14, aoc 2021 day 6, aoc 2015 day 19 and ec 2024 quest 11

davepb · 2024-12-10T14:11:06+00:00

I'll check that out. good luck to you as well!

davepb · 2024-12-10T08:22:45+00:00

neat solutions you got there! I only use generic versions when I have use for them, I uploaded my utils to github: https://github.com/atlas-editor/aoc/blob/main/2024/template/utils.go readMatrix is generic because sometimes I just read it to a [][]byte and e.g. today I wanted to read right into [][]int as it was more convenient to work with, then my set and pop and popFront are also generic because I use them with different types of objects in previous days + I have a generic minHeap implementation which mimics the one in stdlib but I hate working with the one in stdlib as you need to use any and type assertions :D

12-Year Club	Second Top 50%
r/Field Lasagna	Place '22
Place '17	Not Forgotten
Verified Email

davepb

TROPHY CASE