Welcome everyone to the 2023 advent of code! Thank you all for stopping by and participating in it in programming.dev whether youre new to the event or doing it again.
This is an unofficial community for the event as no official spot exists on lemmy but ill be running it as best I can with Sigmatics modding as well. Ill be running a solution megathread every day where you can share solutions with other participants to compare your answers and to see the things other people come up with
Day 1: Trebuchet?!
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)
- Code block support is not fully rolled out yet but likely will be in the middle of the event. Try to share solutions as both code blocks and using something such as https://topaz.github.io/paste/ or pastebin (code blocks to future proof it for when 0.19 comes out and since code blocks currently function in some apps and some instances as well if they are running a 0.19 beta)
FAQ
- What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
- Where do I participate?: https://adventofcode.com/
- Is there a leaderboard for the community?: We have a programming.dev leaderboard with the info on how to join in this post: https://programming.dev/post/6631465
🔒This post will be unlocked when there is a decent amount of submissions on the leaderboard to avoid cheating for top spots
🔓 Edit: Post has been unlocked after 6 minutes
My solutin in Elixir for both part 1 and part 2 is below. It does use regex and with that there are many different ways to accomplish the goal. I’m no regex master so I made it as simple as possible and relied on the language a bit more. I’m sure there are cooler solutions with no regex too, this is just what I settled on:
https://pastebin.com/u1SYJ4tY
defmodule AdventOfCode.Day01 do def part1(args) do number_regex = ~r/([0-9])/ args |> String.split(~r/\n/, trim: true) |> Enum.map(&first_and_last_number(&1, number_regex)) |> Enum.map(&number_list_to_integer/1) |> Enum.sum() end def part2(args) do number_regex = ~r/(?=(one|two|three|four|five|six|seven|eight|nine|[0-9]))/ args |> String.split(~r/\n/, trim: true) |> Enum.map(&first_and_last_number(&1, number_regex)) |> Enum.map(fn number -> Enum.map(number, &replace_word_with_number/1) end) |> Enum.map(&number_list_to_integer/1) |> Enum.sum() end defp first_and_last_number(string, regex) do matches = Regex.scan(regex, string) [_, first] = List.first(matches) [_, last] = List.last(matches) [first, last] end defp number_list_to_integer(list) do list |> List.to_string() |> String.to_integer() end defp replace_word_with_number(string) do numbers = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"] String.replace(string, numbers, fn x -> (Enum.find_index(numbers, &(&1 == x)) + 1) |> Integer.to_string() end) end end