26 lines
759 B
Plaintext
26 lines
759 B
Plaintext
defmodule Factorial do
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# Simple recursive function
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def fac(0), do: 1
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def fac(n) when n > 0, do: n * fac(n - 1)
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# Tail recursive function
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def fac_tail(0), do: 1
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def fac_tail(n), do: fac_tail(n, 1)
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def fac_tail(1, acc), do: acc
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def fac_tail(n, acc) when n > 1, do: fac_tail(n - 1, acc * n)
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# Tail recursive function with default parameter
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def fac_default(n, acc \\ 1)
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def fac_default(0, acc), do: acc
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def fac_default(n, acc) when n > 0, do: fac_default(n - 1, acc * n)
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# Using Enumeration features
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def fac_reduce(0), do: 1
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def fac_reduce(n) when n > 0, do: Enum.reduce(1..n, 1, &*/2)
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# Using Enumeration features with pipe operator
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def fac_pipe(0), do: 1
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def fac_pipe(n) when n > 0, do: 1..n |> Enum.reduce(1, &*/2)
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end
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