Factorial in Elixir

Published on 28 April 2022 (Updated: 27 November 2022)

Factorial in Elixir

Welcome to the Factorial in Elixir page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

defmodule Factorial do
  def main(args) do
    args
    |> List.first
    |> as_integer
    |> get
    |> IO.puts()
  end

  def get(0, acc) do
    acc
  end

  def get(n, acc) do
    get(n - 1, acc * n)
  end

  def get(n) when not is_integer(n) or n < 0 do
    "Usage: please input a non-negative integer"
  end

  def get(n) do
    get(n, 1)
  end

  def as_integer(n) do
    try do
        String.to_integer(n)
    rescue
        ArgumentError -> -1
    end
  end
end

Factorial.main(System.argv())

Factorial in Elixir was written by:

If you see anything you'd like to change or update, please consider contributing.

Note: The solution shown above is the current solution in the Sample Programs repository as of Oct 16 2019 14:19:14. The solution was first committed on Oct 12 2019 09:32:34. As a result, documentation below may be outdated.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

No 'How to Run the Solution' section available. Please consider contributing.