31 lines
786 B
Elixir
31 lines
786 B
Elixir
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defmodule Raindrops do
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@doc """
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Returns a string based on raindrop factors.
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- If the number contains 3 as a prime factor, output 'Pling'.
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- If the number contains 5 as a prime factor, output 'Plang'.
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- If the number contains 7 as a prime factor, output 'Plong'.
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- If the number does not contain 3, 5, or 7 as a prime factor,
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just pass the number's digits straight through.
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"""
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@results [
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{3, "Pling"},
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{5, "Plang"},
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{7, "Plong"}
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]
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@spec convert(pos_integer) :: String.t()
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def convert(number) do
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@results
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|> Enum.map_join(&mapper(number, &1))
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|> case do
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"" -> Integer.to_string(number)
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result -> result
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end
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end
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defp mapper(number, {factor, value}) do
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if rem(number, factor) == 0, do: value, else: ""
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end
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end
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