文法G=(E,+,,(,),a,P,E)，其中P由下列产生式组成E->E+E|E

发布时间：2017-07-15 11:32 │ 来源：www.tikuol.com

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问题：

文法G=(E,+,*,(,),a,P,E)，其中P由下列产生式组成E->E+E|E*E|(E)|a.它生成由a,+,*,(,)组成的算术表达式，该文法在乔姆斯基分层中属于 (66) 型文法，其对应的自动机是 (67) ，如产生句子a*a+a，它的派生树是 (68) ，且最左派生由 (69) 种，该文法是 (70) 。

（68）处填（）。

A．二叉树

B．完全有界自动机

C．三叉树

D．四叉树

考点：计算机软件水平考试中级软件设计师中级软件设计师上午试题

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     Home, sweet home
     It was December 22. The cold wind swept the countless snowflakes (雪花) across my front yard. My
dad was there sweeping the   1 . His nose was   2    as a cherry. With every breath he took, a white puff
(水气) ran into the air.
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( )2. A. red
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( )4. A. wish
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