怎麼个加法...?http://yun.baidu.com/share/link?shareid=714753780&uk=220209607&third=0&dir=%2F%E6%88%91%E7%9A%84%E8%A7%86%E9%A2%91%2F%E4%BC%9A%E9%95%BF%E5%A4%A7%E4%BA%BA%E6%98%AF%E5%A5%B3%E4%BB%86%2F%E7%BB%AF%E9%97%BB%E7%94%B7%E5%AD%A9&page=1&adapt=pc&fr=ftw