Advent of Code 2021

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  • adventofcode

    Advent of Code solutions of 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022 and 2023 in Scala (by sim642)

  • adventlang

    🎅 A programming language (+ code playground) for Advent of Code.

    Some create a language just for AoC, for example:


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  • Advent_of_Code_in_Pascal

    My solutions to the Advent of Code, in Free Pascal

    I'll balance that out for you, I do my programming in Pascal. I'm going through the old ones as well, hoping to back-fill in answers to all of them.

  • advent-of-code-2021

    🎄 My Advent of Code solutions in Rust.

    Last year I solved all puzzles in less than 1 second. This year, for lack of a better goal, I'll be trying to do the same:

  • AdventOfCode2020

    Solutions to all 25 AoC 2020 problems in Rust :christmas_tree:

    It actually was on day 19, it's just that puzzle #13 was the 19th puzzle given out [1]. I'm not sure why the numbers didn't come in order last year.

    [1]: shows the number order

  • advent-of-code-2021

    Advent of Code 2021 in TypeScript. (by boutell)

    Tackling it in TypeScript this year, which is interesting because I haven't used TypeScript before (I'm experienced with JavaScript). This is a good way to really drill it into my fingertips.

    If you care to follow along:

  • aocrunner

    Advent of Code runner

  • WorkOS

    The modern API for authentication & user identity. The APIs are flexible and easy-to-use, supporting authentication, user identity, and complex enterprise features like SSO and SCIM provisioning.

  • aoc2021

    Advent of code 2021 (by melted)

    I'm also doing it in Typescript this year, but I'm doing it in the browser to get a little modern web experience (I'm a C++ developer by day). I have a pretty nifty setup with Snowpack that will rebuild it and refresh the browser automatically when I save, and a little scaffolding for making a widget for a problem, I don't use a framework:

  • ws-challenges

    Solutions for Project Euler, Advent of Code, and Rosetta Code in Whitespace

  • coalton

    Coalton is an efficient, statically typed functional programming language that supercharges Common Lisp.

    Type annotations, as in any good ML, are optional (except when there are polymorphism bugs, like one found during AoC!). Unlike Haskell, purity isn't demanded.

    There's a small contest [2] with all sorts of prizes for doing AoC in Coalton and contributing back to the project through tutorials, PRs, and bug reports.

    [0] They hang out on Discord



  • advent-of-code

    My Advent of Code solutions in Python (plus step-by-step explanations) (by xavdid)

    AoC is one of my favorite events of the year. I find the puzzles to be much more approachable than things like Project Euler. I regularly credit my yearly participation for making me a better programmer.

    I also do a daily writeup of my solution, which helps make sure I understand the problem and help others who are learning. I found it super rewarding last year, so I'm doing it again this year. They're in my GH repo. Here's today's:

    My big tip is that you probably don't need to worry about competing for the leaderboard (unless you really want to). Go at your own pace, don't stay up weird hours, and take a break.

  • aoc

    Advent of Code Solutions (by linus)

    While I agree four minutes is very quick, if you take into account that no side fits with more than one other side, and that the sides (#, .) may just as well be interpreted as binary numbers, it becomes an issue of parsing, mostly, and then matching numbers.

    I remember being flabbergasted at first, and then realizing the above. My solution is here:

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