RosettaCodeData/Task/24-game/Elixir/24-game.ex

40 lines
1.0 KiB
Elixir

defmodule Game24 do
def main do
IO.puts "24 Game"
play
end
defp play do
IO.puts "Generating 4 digits..."
digts = for _ <- 1..4, do: Enum.random(1..9)
IO.puts "Your digits\t#{inspect digts, char_lists: :as_lists}"
read_eval(digts)
play
end
defp read_eval(digits) do
exp = IO.gets("Your expression: ") |> String.strip
if exp in ["","q"], do: exit(:normal) # give up
case {correct_nums(exp, digits), eval(exp)} do
{:ok, x} when x==24 -> IO.puts "You Win!"
{:ok, x} -> IO.puts "You Lose with #{inspect x}!"
{err, _} -> IO.puts "The following numbers are wrong: #{inspect err, char_lists: :as_lists}"
end
end
defp correct_nums(exp, digits) do
nums = String.replace(exp, ~r/\D/, " ") |> String.split |> Enum.map(&String.to_integer &1)
if length(nums)==4 and (nums--digits)==[], do: :ok, else: nums
end
defp eval(exp) do
try do
Code.eval_string(exp) |> elem(0)
rescue
e -> Exception.message(e)
end
end
end
Game24.main