Advent of code 2024 - Day 3

Mix.install([
  {:kino, "~> 0.14.2"}
])

Part 1

https://adventofcode.com/2024/day/3

textarea = Kino.Input.textarea("Give input:")

input = Kino.Input.read(textarea)

matches = Regex.scan(~r/mul\((\d{1,3}),(\d{1,3})\)/, input)

Enum.map(matches, fn match -> String.to_integer(Enum.at(match, 1)) * String.to_integer(Enum.at(match, 2)) end)
|> Enum.sum

Part 2

# split on do() and don't()
# prefix with do() in the first row

["" | rest] = String.split("do()" <> input, ~r/do(n't)?\(\)/, include_captures: true)

matches2 =
  Enum.chunk_every(rest, 2)
  |> Enum.filter(fn [cmd, _match] -> cmd == "do()" end)
  |> Enum.flat_map(fn [_, match] -> Regex.scan(~r/mul\((\d{1,3}),(\d{1,3})\)/, match) end)

Enum.map(matches2, fn match ->
  String.to_integer(Enum.at(match, 1)) * String.to_integer(Enum.at(match, 2))
end)
|> Enum.sum()