Depth first search algorithm with Elixir

dfs.exs

defmodule DFS do
  @moduledoc """
  Depth first search algorithm

  Example

    vertices = %{
      0 => [1, 3],
      1 => [0, 2],
      2 => [1, 3],
      3 => [2]
    }

    DFS.perform(0, 3, vertices)
    "Visited 3"
    "Visited 2"
    "Visited 1"
    "Visited 0"
    true
  """
  @spec perform(integer(), integer(), map()) :: boolean()
  def perform(source, destination, vertices) do
    recursive(source, destination, vertices)
  end

  defp recursive(vertex, destination, vertices, visited \\ MapSet.new()) do
    result =
      if vertex == destination do
        true
      else
        visited = MapSet.put(visited, vertex)

        adjacency_vertices = Enum.filter(vertices[vertex], &(not MapSet.member?(visited, &1)))

        Enum.reduce_while(adjacency_vertices, false, fn adjacency, _acc ->
          result = recursive(adjacency, destination, vertices, visited)

          if result do
            {:halt, true}
          else
            {:cont, false}
          end
        end)
      end

    IO.inspect("Visited #{vertex}")
    result
  end
end