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

Solution Threads

M	T	W	T	F	S	S
1	2	3	4	5	6	7
8	9	10	11	12

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Keep all content related to advent of code in some way
If what youre posting relates to a day, put in brackets the year and then day number in front of the post title (e.g. [2024 Day 10])
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Credits

Icon base by Lorc under CC BY 3.0 with modifications to add a gradient

console.log('Hello World')

founded 2 years ago

MODERATORS

Ategon@programming.dev

Sigmatics@lemmy.ca

CameronDev@programming.dev

hades@programming.dev

🧑 - 2025 DAY 2 SOLUTIONS - 🧑 (programming.dev)

submitted 2 days ago by CameronDev@programming.dev to c/advent_of_code@programming.dev

29 comments fedilink hide all child comments

Day 2: Gift Shop

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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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[–] strlcpy@lemmy.sdf.org 4 points 1 day ago* (last edited 1 day ago)

C

There are interesting analytical observations to be made about the problem to sidestep most of the actual iteration, but I wasn't up to working it all out and the runtime was pretty much instant anyway.

Here's my original solution with ints, using divions with powers of 10 to do the splitting: day02-u64.c

But I'm only doing the C implementations to prototype my assembly solutions, and dealing with 64-bit numbers, especially divisions, on x86-16 is painful, so I rewrote the solution using a fixed-length string "numbers" instead: day02.c

Still working on the assembly version

Assembly update: have part 1 working now! It's dog slow on DOSBox, but on QEMU it's good: day02.asm