将四个元素a，b，c，d分成非空的两组，不计组内顺序和组间顺序，共有（4)种分组 方法。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29738' and id < 2415726 and id<>'2415726' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29738' and id > 2415726 and id<>'2415726' order by id asc limit 5