string(266) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E9%93%B6%E8%A1%8C%E5%88%A9%E7%8E%87%E8%AE%A1%E7%AE%97%E5%85%AC%E5%BC%8F%E5%8F%8A%E4%BE%8B%E9%A2%98 => Failed to connect to 101.91.112.32 port 38195: Connection refused"
银行利率计算公式及例题
