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2024/day01.livemd
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       # Day 01

     

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       ```elixir

     

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       Mix.install([:kino_aoc])

     

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       ```

     

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       ## Section

     

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       <!-- livebook:{"attrs":"eyJhc3NpZ25fdG8iOiJwdXp6bGVfaW5wdXQiLCJkYXkiOiIxIiwic2Vzc2lvbl9zZWNyZXQiOiJBRFZFTlRfT0ZfQ09ERV9TRVNTSU9OIiwieWVhciI6IjIwMjQifQ","chunks":null,"kind":"Elixir.KinoAOC.HelperCell","livebook_object":"smart_cell"} -->

     

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       ```elixir

     

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       {:ok, puzzle_input} =

     

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         KinoAOC.download_puzzle("2024", "1", System.fetch_env!("LB_ADVENT_OF_CODE_SESSION"))

     

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       ```

     

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       ```elixir

     

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       {left, right} =

     

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       puzzle_input

     

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       |> String.split("\n", trim: true)

     

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       |> Enum.map(fn line ->

     

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         line

     

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         |> String.split(" ", trim: true)

     

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         |> Enum.map(&String.to_integer/1)

     

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         |> List.to_tuple()

     

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       end)

     

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       |> Enum.unzip()

     

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       ```

     

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       ## Part 1

     

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       ```elixir

     

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       left

     

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       |> Enum.sort()

     

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         |> Enum.zip_with(Enum.sort(right), &abs(&1 - &2))

     

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       |> Enum.sum()

     

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       ```

     

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       ## Part 2

     

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       ```elixir

     

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       freq_left = Enum.frequencies(left)

     

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       freq_right = Enum.frequencies(right)

     

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       freq_left

     

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       |> Enum.map(fn {id, n} -> id * n * Map.get(freq_right, id, 0) end)

     

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       |> Enum.sum()

     

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       ```

     

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