defmodule Main do
  def main do
    [a, b] = IO.gets("") |> String.trim() |> String.split(" ")
    a = String.to_integer(a)
    b = String.to_float(b)

    multiplication(a, b) |> IO.puts()
  end

  @doc """
  Multiplication

  ## Examples

      iex> Multiplication3.multiplication(198, 1.10)
      217
      iex> Multiplication3.multiplication(1, 0.01)
      0
      iex> Multiplication3.multiplication(1000000000000000, 9.99)
      9990000000000000

  """
  def multiplication(a, b) do
    (a * trunc(b * 100)) |> Kernel./(100) |> trunc
  end
end