某二叉树的前序序列为ABDFHCEG,中序序列为HFDBACEG。该二叉树按层次输出（同一层从左到右）的序列为（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='28853' and id < 2351162 and id<>'2351162' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='28853' and id > 2351162 and id<>'2351162' order by id asc limit 5