string(239) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%A4%8D%E6%95%B0%E4%B9%98%E9%99%A4%E6%B3%95%E7%9A%84%E8%AE%A1%E7%AE%97%E6%96%B9%E6%B3%95 => Received HTTP code 403 from proxy after CONNECT"
复数乘除法的计算方法
