24
submitted 2 weeks ago* (last edited 2 weeks ago) by CameronDev@programming.dev to c/advent_of_code@programming.dev

Day 3: Mull It Over

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)
  • You can send code in code blocks by using three backticks, the code, and then three backticks or use something such as https://topaz.github.io/paste/ if you prefer sending it through a URL

FAQ

you are viewing a single comment's thread
view the rest of the comments
[-] rwdf@lemmy.world 2 points 2 weeks ago* (last edited 2 weeks ago)

Elixir

First time writing Elixir. It's probably janky af.

I've had some help from AI to get some pointers along the way. I'm not competing in any way, just trying to learn and have fun.

~~Part 2 is currently not working, and I can't figure out why. I'm trying to just remove everything from "don't()" to "do()" and just pass the rest through the working solution for part 1. Should work, right?

Any pointers?~~

edit; working solution:

defmodule Three do
  def get_input do
    File.read!("./input.txt")
  end

  def extract_operations(input) do
    Regex.scan(~r/mul\((\d{1,3}),(\d{1,3})\)/, input)
    |> Enum.map(fn [_op, num1, num2] ->
      num1 = String.to_integer(num1)
      num2 = String.to_integer(num2)
      [num1 * num2]
    end)
  end

  def sum_products(ops) do
    List.flatten(ops)
    |> Enum.filter(fn x -> is_integer(x) end)
    |> Enum.sum()
  end

  def part1 do
    extract_operations(get_input())
    |> sum_products()
  end

  def part2 do
    String.split(get_input(), ~r/don\'t\(\)[\s\S]*?do\(\)/)
    |> Enum.map(&extract_operations/1)
    |> sum_products()
  end
end

IO.puts("part 1: #{Three.part1()}")
IO.puts("part 2: #{Three.part2()}")

[-] vole@lemmy.world 2 points 2 weeks ago

Part 2 is currently not working, and I can’t figure out why. I’m trying to just remove everything from “don’t()” to “do()” and just pass the rest through the working solution for part 1. Should work, right?

I think I had the same issue. Consider what happens if there isn't a do() after a don't().

[-] rwdf@lemmy.world 1 points 2 weeks ago

Ah, yes, that's it. The lazy solution would be to add a "do()" to the end of the input, right? Haha

[-] rwdf@lemmy.world 1 points 2 weeks ago

It was actually a line break that broke the regex. Changing from a "." to "[\s\S]" fixed it.

this post was submitted on 03 Dec 2024
24 points (96.2% liked)

Advent Of Code

920 readers
65 users here now

An unofficial home for the advent of code community on programming.dev!

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.

AoC 2024

Solution Threads

M T W T F S S
1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25

Rules/Guidelines

Relevant Communities

Relevant Links

Credits

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

console.log('Hello World')

founded 1 year ago
MODERATORS