string(276) "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%E7%9A%84%E4%B9%98%E9%99%A4%E6%B3%95%E8%BF%90%E7%AE%97%E6%B3%95%E5%88%99%E6%95%99%E6%A1%88 => Failed to connect to 101.89.117.144 port 38208: Connection refused"
复数的乘除法运算法则教案
