Max Product Of Three

Elixir Max Product Of Three

defmodule MaxProductOfThree do
  def max_product_of_three(a) do
    sorted = Enum.sort(a)
    c = length(sorted)

    max(
      Enum.at(sorted, c - 1) * Enum.at(sorted, c - 2) * Enum.at(sorted, c - 3),
      Enum.at(sorted, 0) * Enum.at(sorted, 1) * Enum.at(sorted, c - 1)
    )
  end
end

This checks the useful extremes, because the best product can come from either the three largest numbers or two negatives plus one large positive.