Thanks! Here’s to another year of giving up after a week.

I am going to write up my Haskell solution at some point, but I liked this:

CREATE TABLE day_01 (v INT NOT NULL UNIQUE);
COPY day_01 FROM 'Projects/AOC/2020/data/Day01.txt';

SELECT 1 AS part, a.v * b.v AS answer
  FROM day_01 a CROSS JOIN day_01 b 
 WHERE a.v <> b.v AND a.v + b.v = 2020
 UNION
SELECT 2 AS part, a.v *  b.v * (2020 - a.v - b.v) AS answer
  FROM day_01 a CROSS JOIN day_01 b
 WHERE a.v <> b.v
   AND 2020 - a.v - b.v > 0
   AND EXISTS (SELECT 1 FROM day_01 WHERE v = 2020 - a.v - b.v);

And it’s crazy fast:

   part |  answer
 -------+----------
      1 |   800139
      2 | 59885340
(2 rows)

Time: 6.732 ms

I’m just going to say that the title might be clickbait, because it sounds like “coming up with a solution for a problem in under a second”. Of course, it’s also my fault, for being naive enough to belive it. Perhaps I was expecting some APL-wizardry.

You can also join #lobsters-advent on freenode to chat about problems.

Since the first one filled up, I set up a second one, code 400344-db76bd5d to join.

I’m trying to do it in machine code, but ok :)

This was a pretty fun read.

Regarding “readable and elegant” as being a virtue of a good language. As someone who doesn’t know Raku and isn’t familiar with perl, I have to admit that your example, for me anyway, was completely impenetrable. I’m not trying to burst your bubble, but on the other hand demonstrate how horribly subjective these things are. I’m in the process of trying to learn Haskell, and the example you gave actually had a very Haskell-esk/FP kind of feel to it.

Long story short, I might look into Raku.

This was really pleasant to read and was nice because it sounds like the author really just enjoys using Raku. Which is, perhaps, an underrated feature of our tools.

Last year was the first year I finished all 25 days, let’s see if I can keep up this year as well. Doing it in Rust to see if I hate it a little less after forcing myself to use it for a while.

Can you be on more than one leaderboard at the same time?

I took a look at Raku for the first time in a long time for this year’s advent.

I’ve already had several omg/wtf/wow moments. There seems to be a lot of very mature, interesting work here.

Lots of people will hate it (those who dislike sigils, more than one way to do things etc), but when I read that the for loop takes an iterable and a block, so you can use a “pointy block” and the arrow in the example code I was looking at was part of the block syntax, I was pretty amazed.

It seems like the language is built out of an interesting set of abstractions. I don’t know if I’m going to deep dive, but it is seems pretty exciting.

As someone who prefers book to learn a new programming language, which one would be the best? I see there is “Learning Perl 6” and the brand new “Raku Fundamentals”.

Since lobsters is publicly viewable, I don’t think that leaderboard is very private.

Today was fun!

I had seen the links and commentary in years past, but I always had something else to do. This year I might do a few. It reminds me of “nerd crosswords”, ie, fun little intellectual games to get the juices flowing first thing in the morning.

I’ll share my repo – I’m learning Rust right now and needed something to force me to write code in it so I can move out of the “throwing & at the code until the compiler stops yelling at me” phase of learning Rust :D

https://github.com/3digitdev/aoc2020

This post is day 1 of the 2020 Raku Advent Calendar, so there will be another 24 daily posts on Raku-related topics between now and Christmas.

The article links to the Advent of Raku 2020 Git repo, which is collecting Raku solutions to Advent of Code. The day one solutions have already presented multiple different approaches – just as you might expect from Raku!

Question from a noob: are we supposed to upload our work to GitHub? I saw some other lobsters posting links. If so, is there a place to register your repo once you upload it?

It’s full, :-(

Hey all, my solutions will be here: https://github.com/lindgrenj6/adventofcode_2020

I’m doing it in elixir this year, kind of fell off last year but going to attempt to do at least 2 weeks this year!

Thanks for stepping up. I’ve joined!

This is my first year doing it! I’m trying to use J. My only other experience with J is some Project Euler problems.

It’s fun thinking spatially and coming up with a concise solution, but this makes me realize how absolutely dependent I am on Google/StackOverflow to learn by example. There is some stuff out there for J, but compared to more popular languages it’s nothing. Even for simple things like “split a string on a multi-character delimiter” (I eventually found the built-in splitstring and the load 'regex' library). I think it will get easier once I memorize more of NuVoc.

I’m in!

Reposting @syn-ack’s text story because the merged story view doesn’t show it.

Hey there! I’ve created a private leaderboard for Lobste.rs on AoC2020. Use the code 989653-afc97283 to join.

Please submit AoC links in comments here. As usual for story merging, we’ll do one story per week.

I’m still working on getting my blog together for it, but I’m doing all of the problems in COBOL on IBM i as a way to learn both COBOL and IBM i. It’s been relatively straightforward so far, but I expect things to get much trickier soon.

Once I get it published, the blog will be available at https://thequux.github.io

My solutions are / will be at: https://github.com/joelgrus/advent2020

I also stream while I’m trying to solve the problems, those videos end up here: https://www.youtube.com/playlist?list=PLeDtc0GP5ICmVrjHJrIiDZFW_xr__Ifqk

I wrote a post about my solutions for day 1 and 2: https://jlelse.blog/dev/aoc-2020-day1-2

I will continue posting solutions to the dev section of my blog: https://jlelse.blog/dev

I’m using Clojure this year - check my solutions at https://github.com/st3fan/aoc/tree/master/2020/advent-of-code/src/advent_of_code

I’m trying out this year’s puzzles in OCaml: https://github.com/yawaramin/aoc2020/

This year trying not to worry about generality too much, and just solving the specific puzzle itself. Also trying to think up ways to avoid being ‘accidentally quadratic’. Not sure how long I can keep it up, but so far so good.

Thanks for putting this together! I joined. Looking forward to it.

I did question 1a, 3a and 3b without writing code, using brain, fingers, kakoune editor and calculator.

I’m not gonna try join a leaderboard, since I’m using the AoC to teach myself Rust.

https://github.com/offbyone/advent-of-code-2020 though, if anyone wants to watch a Python dev figure out this “Rust” thing :)

Wow! All y’all are impressively fast! I’m happy to not be last. :)

(That’s in reference to tonight’s scores. For readers from the future, this is the second night but the first that there are scores, since the first night’s scores were disqualified due to server capacity issues.)

My day 3 in Haskell baby-talk. I’m really looking forward to when the wheels come off.

I’m solving mine with Emacs Lisp and literate programming: https://tildegit.org/acdw/aoc-2020/src/branch/main/aoc.org

Linking my 2020 AoC file (Clojure): https://github.com/neeasade/AdventOfCode/blob/master/src/aoc/2020.clj

Putting my words where my mouth is:

• blog entry (will be updated as time passes): http://gerikson.com/blog/comp/Advent-of-Code-2020.html
• repo (trigger warning: PERL 5 content): https://github.com/gustafe/aoc2020

The irc channel is a true gem! Great discussions.

I will be blogging on progress (and learning) on https://bulters.dev and code will be up on https://GitHub.com/bulters/aoc20

Good luck to all participants!

Thanks, joined as well.

Just joined! Every year I end up doing only a few of these but let’s see how it goes this year.

Well, I’m going to try this in Janet, and only do it on weekends: https://github.com/yumaikas/aoc2020

Thanks, just joined. 2 hours to go!