def filter(list, params) result = [] list.each do |element| case params when :aho if element.include?('3') || element.to_i.modulo(3) == 0 result << element end when :even if element.to_i.even? result << element end when :odd if element.to_i.odd? result << element end else result << element end end result end def show_html(list) puts '' puts '

#{element}

' puts '' end #### :even ##### list = %w(18 22 11 73 91 38 24 17) filtered_list = filter(list, :even) show_html(filtered_list)