Aurélien Geron
42 lines
880 B
Elixir
42 lines
880 B
Elixir
defmodule Aoc2024.Day01 do
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def parse(input) do
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numbers =
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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(~r/\s+/)
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|> Enum.map(fn int_str ->
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case int_str |> Integer.parse() do
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{int, ""} -> int
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_ -> raise "Invalid integer #{int_str}"
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end
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end)
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end)
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numbers
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|> Enum.map(&List.to_tuple/1)
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|> Enum.unzip()
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end
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def part1({col0, col1}) do
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sorted_col0 = col0 |> Enum.sort()
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sorted_col1 = col1 |> Enum.sort()
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Enum.zip(sorted_col0, sorted_col1)
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|> Enum.map(fn {val0, val1} ->
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abs(val0 - val1)
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end)
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|> Enum.sum()
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end
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def part2({col0, col1}) do
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col0
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|> Enum.map(fn val0 ->
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count = Enum.count(col1, fn val1 -> val0 == val1 end)
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count * val0
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end)
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|> Enum.sum()
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end
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end
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