Day 1: Historian Hysteria
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FAQ
- What is this?: Here is a post with a large amount of details: https://programming.dev/post/22323136
- 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
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Elixir
defmodule AdventOfCode.Solution.Year2024.Day01 do
use AdventOfCode.Solution.SharedParse
@impl true
def parse(input) do
numbers =
input
|> String.split("\n", trim: true)
|> Enum.map(fn l -> String.split(l, ~r/\s+/) |> Enum.map(&String.to_integer/1) end)
{Stream.map(numbers, &Enum.at(&1, 0)), Stream.map(numbers, &Enum.at(&1, 1))}
end
def part1({left, right}) do
Enum.zip_reduce(Enum.sort(left), Enum.sort(right), 0, &(&3 + abs(&1 - &2)))
end
def part2({left, right}) do
freq = Enum.frequencies(right)
left |> Stream.map(&(&1 * Map.get(freq, &1, 0))) |> Enum.sum()
end
end
1 point