试题1

程序设计语言中 （ ） 。
A、while循环语句的执行效率比do-while循环语句的执行效率高
B、while循环语句的循环体执行次数比循环条件的判断次数多1，而do-while语句的循环体执行次数比循环条件的判断次数少1
C、while语句的循环体执行次数比循环条件的判断次数少1，而do-while语句的循环体执行次数比循环条件的判断次数多1
D、while语句的循环体执行次数比循环条件的判断次数少1，而do-while语句的循环体执行次数等于循环条件的判断次数

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试题2

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试题3

一个文法G=(N，T，P，S)，其中N是非终结符号的集合，T是终结符号的集合，P是产生式集合，S是开始符号，令集合V=N∪T，那么G所描述的语言是（ ）的集合。
A、由S推导出的所有符号串 
B、由S推导出的所有终结符号串 
C、V中所有符号组成的符号串 
D、V的闭包中的所有符号串 

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试题4

why have formal documents 
first, writing the decisions down is essential.Only when one writes do the gaps appear and the    (1)    protrude(突出).The act of writing turns out to require hundreds of mini-decisions.and it is the existence of these that distinguishes clear.exact policies from fuzzy ones.
Second.the documents will communicate the decisions to others. The manager will be continually amazed that poliaes he took for common knowledge are totally unknown by some member of his team . Since his fundamentaljob is to keep everybody going in the  (2)directon. his chief daily task will be communication, not decision-making,and his documents will immensely   (3)   this load.
Finally.a manager,s documents give him a data base and checklist. By reviewing them (4)he sees where he is. and he sees what changes of emphasis or shifts in direction are needed.
The task of the manager is to develop a plan and then to realize it. But only the written plan is precise and communicable. Such a plan consists of documents on what.when. how much.where.and who.This small set of critical documents  (5)  much of the manager.s   work.if their comprehensive and critical nature is recognized in the beginning. the manager can approach them as friendly tools rather than annoying busywork. He will set his direction much more crisply and quickly by doing so.
（1）A.inconsistencies
B.consistencies
C.steadiness
D.adaptability
（2）A.other
B.different
C.another
D.same
（3）A.extend
B.broaden
C.lighten
D.release
（4）A.periodically
B.occasionally
C.infrequently
D.rarely
（5）A.decides
B.encapsulates
C.realizes
D.recognizes

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试题5

对以下四个序列用直接插入排序方法由小到大进行排序时，元素比较次数最少的是  （ ）  。
A、89, 27, 35, 78, 41, 15
B、27, 35, 41, 16, 89, 70
C、15, 27, 46, 40, 64, 85
D、90, 80, 45, 38, 30, 25

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试题6

（1）A、0
B、1
C、2
D、3
（2）A、P(S)、V(S)  和 V(S)
B、P(S)、P(S)  和 V(S)
C、V(S)、P(S)  和 P(S)
D、V(S)、V(S)  和 P(S)

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试题7

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试题8

在关系代数运算中，关系S、SP和R如下表所示。若先（1），则可以从S和SP获得R。其对应的关系表达式为（2） 。如下的SQL语句可以查询销售总量大于1000 的部门号。 Select 部门名From S
Where 部门号in (Select 部门号From SP Group by （3）)关系表S 关系表SP 关系表R

（2）
（1）A、对S进行选择运算，再与SP进行自然连接运算
B、对S进行选择运算，再与SP进行自然连接运算，最后进行投影运算
C、对S和SP进行笛卡尔积运算，再对运算结果进行投影运算
D、分别对S和SP进行投影运算，再对运算结果进行笛卡尔积运算
（2）A. A
B. B
C. C
D. D
（3）A、部门号 where sum( 销售量)>1000
B、部门号 having sum( 销售量)>1000
C、商品号 where sum( 销售量)>1000
D、商品号 having sum( 销售量)>1000

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试题9

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试题10

在YUV彩色空间中对YUV分量进行数字化，对应的数字化位数通常采用Y:U:V=（ ）。
A、8:4:2 
B、8:4:4 
C、8:8:4 
D、4:8:8 

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