[Elixir] adventofcode 2018 Day 1

2018_d1.exs

# Part 1
data = ['+3', '-3']

data 
  |> Enum.map(&(String.to_integer))
  |> Enum.sum
  
# Part 2

acc = {0, %{}}
data 
  |> Enum.map(&(String.to_integer))
  |> Stream.cycle
  |> Enum.reduce_while(acc, fn x, acc -> 
    {sum, mark} = acc;
    sum = sum + x;
    if Map.has_keys?(mark, sum) do
       IO.puts sum
      {:halt, {sum, mark}}
    else
      {:cont, {sum, mark}}
    end
  end)