gistfile1.rb

class Toss
  attr_accessor :cubes

  #Toss
  def groups_size(n)
    counts = cubes.group_by(&:face_up).map { |face, cubes| [face, cubes.size] }
    counts.select { |face, count| count == n }.map(&:first) 
  end

end

# Module?
def groups_of_size(n)
 @group ||= toss.groups_size(n).size
end


def can_score?
  groups_of_size?(5)
end

def score

 if groups_of_size?(5)
  ....