string(283) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%85%AC%E5%88%86%E5%92%8C%E5%8E%98%E7%B1%B3%E7%9A%84%E6%8D%A2%E7%AE%97%E6%96%B9%E5%BC%8F%E6%98%AF%E4%BB%80%E4%B9%88 => Failed to connect to 14.116.215.7 port 38225: Connection refused"
公分和厘米的换算方式是什么
