hauleth.dev
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2024/day01.livemd
+49
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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```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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