28 lines
551 B
Elixir
28 lines
551 B
Elixir
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defmodule Day1Part2 do
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def run do
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{a, b, c} =
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File.read!("input")
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|> String.trim()
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|> String.split("\n")
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|> Enum.map(&String.to_integer/1)
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|> find_2020()
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IO.puts("#{a} x #{b} x #{c} = #{a * b * c}")
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end
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def find_2020([current | rest]) do
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pair =
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for i <- rest, j <- rest do
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if current + i + j == 2020, do: {i, j}, else: nil
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end
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|> Enum.find(&match?({_, _}, &1))
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case pair do
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{a, b} -> {a, b, current}
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nil -> find_2020(rest)
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end
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end
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end
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Day1Part2.run()
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