对于n个节点的序列，利用shell排序的方法进行比较时，总的关键码的比较次数约为
A. n1.3
B. n2
C. logn2
D. n2/4
查看答案
An appropriate title for the text is most likely to be ______.
A. Fors and Againsts of DNA Testing
B. DNA Testing and It Problems
C. DNA Testing Outside the Lab
D. Lies Behind DNA Testing
It is stated in Paragraph 1 that the construction of a new educational system ______.
A. challenges economists and politicians
B. takes efforts of generations
C. demands priority from the government
D. requires sufficient labor force
The author quotes the example of our ancestors to show that education emerged ______.
A. when people had enough time
B. prior to better ways of finding food
C. when people no longer went hungry
D. as a result of pressure on government
【B20】
A. By accident
B. In time
C. So far
D. Better still
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