44 lines
959 B
Elixir
44 lines
959 B
Elixir
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defmodule Aoc.Solution.Day06 do
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@name "Day 6: Tuning Trouble"
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@behaviour Solution
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@impl Solution
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def get_name, do: @name
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@impl Solution
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def present(solution), do: "Packet marker is at #{solution}"
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@impl Solution
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def present_again(solution), do: "Message marker is at #{solution}"
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@impl Solution
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def parse!(raw) do
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raw |> String.trim() |> String.codepoints()
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end
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@impl Solution
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def solve(datastream) do
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datastream |> packet_marker()
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end
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@impl Solution
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def solve_again(datastream) do
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datastream |> message_marker()
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end
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def packet_marker(datastream) do
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distinct_sequence(datastream, 4)
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end
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def message_marker(datastream) do
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distinct_sequence(datastream, 14)
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end
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def distinct_sequence(datastream, l, start \\ 0) do
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case datastream |> Enum.slice(start, l) |> MapSet.new() |> MapSet.size() do
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^l -> start + l
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_ -> distinct_sequence(datastream, l, start + 1)
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end
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end
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end
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