gistfile1.rb

  def all_children(x=1)
    all = []
    self.children.each do |f| 
        all << f
        if x < 3 then
          root_children = f.all_children(x).flatten
          all << root_children unless root_children.empty?
          x = x + 1 
        end 
    end 
    return all.flatten
  end