问题
4, 5, 7, 9, 13, 15, () A.17 B.19 C
4, 5, 7, 9, 13, 15, ( )
A.17 B.19 C.18 D.20
Fatal error: Uncaught [XSException] ../../../usr/local/xunsearch/sdk/php/lib/XS.php(2559): Connection refused(C#111, localhost:8384)
thrown in /usr/local/xunsearch/sdk/php/lib/XS.php on line 2559