27 lines
379 B
Elixir
27 lines
379 B
Elixir
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defmodule Math do
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@moduledoc """
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Math utilities.
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"""
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alias Extras
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@doc """
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Returns the prime factors for `n`.
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## Examples
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iex> Math.factor(15)
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[3, 5]
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"""
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def factor(1), do: []
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def factor(n) do
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Extras.range(2, n - 1)
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|> Enum.find(&(rem(n, &1) == 0))
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|> case do
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nil -> [n]
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x -> [x | factor(div(n, x))]
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end
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end
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end
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