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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console.log('Hello World')

founded 2 years ago

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Ategon@programming.dev

Sigmatics@lemmy.ca

CameronDev@programming.dev

hades@programming.dev

💂 - 2024 DAY 6 SOLUTIONS - 💂 (programming.dev)

submitted 1 year ago by CameronDev@programming.dev to c/advent_of_code@programming.dev

37 comments fedilink hide all child comments

Day 6: Guard Gallivant

Megathread guidelines

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)
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What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
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[–] aoidenpa@lemmy.world 2 points 1 year ago* (last edited 1 year ago) (1 children)

I created rows and cols vecs that keep places of blocks. When moving, I binary search the row or col, find the block that stops me. So moving whole sections at once. Otherwise used HashSet of pos and dir like you. Also in part 2, place the new block only on the path I take in part1. Part 2 is 26ms.

code

[–] ximtor@lemm.ee 2 points 1 year ago

The binary search sounds smart, would reduce the pathing quite a bit i guess :)

Part 2 i approached quite the same i think, was only a couple lines of code additionally. But running 5ms 5000 times is also gonna take a while..