Exercise

exercise.ex

defmodule Exercise do
  def sort_groups(employee_ids) do
    groups = employee_ids
    |> Enum.shuffle()
    |> Enum.chunk_every(3, 3, [])

    size = Enum.count(employee_ids)
    if rem(size, 3) == 0 do
      groups
    else
      new_group = Enum.at(groups, -1) ++ Enum.at(groups, -2)

      groups
      |> List.replace_at(-2, new_group)
      |> List.delete_at(-1)
    end
  end
end

Exercise.sort_groups([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
Exercise.sort_groups([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
Exercise.sort_groups([0, 1, 2, 3, 4, 5, 6, 7, 8])
Exercise.sort_groups([0, 1, 2, 3, 4, 5, 6, 7])
Exercise.sort_groups([0, 1, 2, 3, 4, 5, 6])