019f8fd211
git-subtree-dir: users/wpcarro git-subtree-mainline:464bbcb15cgit-subtree-split:24f5a642afChange-Id: I6105b3762b79126b3488359c95978cadb3efa789
33 lines
564 B
Elixir
33 lines
564 B
Elixir
defmodule Server do
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@moduledoc """
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Documentation for `Server`.
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"""
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@doc """
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If `n` contains exactly two prime factors, return those prime factors;
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otherwise, return nothing.
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"""
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def semiprime(n) do
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case Cache.get(n) do
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nil ->
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case do_semiprime(n) do
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nil ->
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nil
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res ->
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Cache.put(n, res)
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{:miss, res}
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end
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hit ->
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{:hit, hit}
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end
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end
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defp do_semiprime(n) do
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case Math.factor(n) do
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[_, _] = res -> res
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_ -> nil
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end
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end
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end
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