require 'open-uri' require 'nokogiri' open("http://www.oreilly.co.jp/catalog/") do |f| doc = Nokogiri::HTML.parse f.read prices = doc.css(".price").map{|p| p.text.tr(?,, '').to_i } amount = prices.inject(:+).to_s.gsub(/(\d)(?=(\d{3})+(?!\d))/, '\1,') puts "合計 #{prices.size}冊 #{amount}円" end
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