计算:20+19-18-17+16 + 15-14-13 + 12 + 11…… + 4 + 3-2-1 =( )。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='31033' and id < 2496919 and id<>'2496919' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='31033' and id > 2496919 and id<>'2496919' order by id asc limit 5