allergies.rb

class Allergies

  def initialize(score)
    @score = score
  end

  attr_reader :score

  def allergens
    [ "eggs", "peanuts" ]
  end

  def list
    current_list = []

    allergens.each_with_index do |allergen,index|
      if score & (2 ** index) > 0
        current_list << allergen
      end
    end

    current_list
  end

end