希赛网为大家整理了2017下半年软件设计师考试上午真题,以下为第七部分。
61两个递增序列A 和 B 的长度分别为 m 和 n(m<n 且 m 与 n接近),将二者归井为一个长度为m+n的递增序列。当元素关系为( ),归并过程中元素的比较次数最少。
62. 求解两个长度为n的序列 X和 Y的一个最长公共序列(如序列ABCBDAB和BDCABA的一个最长公共子序列为BCBA)可以采用多种计算方法。如可以采用蛮力法,对X的每一个子序列,判断其是否也是Y的子序列,最后求出最长的即可,该方法的时间复杂度为( )。经分析发现该问题具有最优子序列,可以定义序列成都分别为i和j的两个序列X和Y的最长公共子序列的成都为C[I,j],如下式所示。
A.O(n?)
B.O(n?lgn)
C.O(n?)
D.O(n2^)
A.O(n?)
B.O(n?lgn)
C.O(n?)
D.O(n2^)
64. 现需要对一个基本有序的数组进行排序。此时最适宜采用的算法为( )排算法,时间复杂度为( )。
A.插入
B.快速
C.归并
D.堆
A.O(n)
B.O(nlgn)
C.O(n?)
D.O(n?lgn)
66.相比于TCP ,UDP的优势为( )。
A.可靠传输
B.快消较小
C.拥塞控制
D.流量控制
67.若一台服务器只开放了25和110两个端口,那么这台服务器可以提供( )服务。
A.E-Mail
B.WEB
C.DNS
D.FTP
68.SNM P是一种异步请求/响应协议,采用( )协议进行封装。
A.IP
B.ICMP
C.TCP
D.UDP
69. 在一台安装好TCP/IP协议的计算机上,当网络连接不可用时,为了测试编写好的网络程序,通常使用的目的主机 IP地址为( )。
A.0.0.0.0
B.127.0.0.0
C.10.0.0.1
D.210.225.21.255/24
70.测试网络连通性通常采用的命令是( )。
A.Nestar
B.Ping
C.Mscinfug
D.Cmd
The development of the Semantic Web proceeds in steps, each step building a layer on top of another. The pragmatic justification for this approach is that it is easier to achieve ( )on small steps, whereas it is much harder to get everyone on board if too much is attempted. Usually there are several research groups moving in different directions; this ( ) of ideas is a major driving force for scientific progress. However,from an engineering perspective there is a need to standardize. So, if most researchers agree on certain issues and disagree on others, it makes sense to fix the point of agreement. This way, even if the more ambitious research efforts should fai1, there wil1 be at least( )positive outcomes.
Once a ( )has been established ,many more groups and companies will adopt it, instead of waiting to see which of the alternative research lines will be successful in the end. The nature of the Semantic Web is such that companies and single users must build tools, add content, and use that content. We cannot wait until the full Semantic Web vision materializes-it may take another ten years for it to be realized to its full( )(as envisioned today, of course)。
A.conflicts
B.consensus
C.success
D.disagreement
A.competition
B.agreement
C.cooperation
D.collaboration
A.total
B.complete
C.partial
D.entire
A.technology
B.standard
C.pattern
D.model
A.area
B.goal
C.object
D.extent