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Shell排序、快速排序、堆排序的稳定性如何 (58) 。若要尽可能的完成对实数数组的排序,且要求排序是稳定的,则应选 (59) 。若用插入排序算法对n个记录进行排序,最佳情况下,对关键字进行的比较次数为 (60) 。对于多关键字而言, (61) 是一种方便而又高效的文件组织方式。若用冒泡排序对关键字序列19,16,11,8,5,3从小到大进行排序,则需要次数为 (62) 。 61()

A. 顺序文件
B. 索引文件
C. 散列文件
D. 倒排文件

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阅读下面这篇短文,短文后有2项测试任务:(1)第23~26题要求从所给的6个选项中为规定段每段选择1个正确的小标题;(2)第27~30题要求从所给的6个选项中选择4个正确选项,分别完成每个句子。 There are now over 700 million motor vehicles in the world-and the number is rising by more than 40 million each year. The average distance driven by car users is growing too-from 8 km a day per person in western Europe in 1965 to 25 km a day in 1995. This dependence on motor vehicles had given rise to major problems, including environmental pollution, depletion of oil resources, traffic congestion and safety.2. Until a hundred years ago, most journeys were in the 20 km range, the distance conveniently accessible by horse. Heavy freight could only be carried by water or rail. The invention of the motor vehicle brought personal mobility to the masses and made rapid freight delivery possible over a much wider area. Today 90 per cent of inland freight in the United Kingdom is carried by road. Clearly the world cannot revert to the horse-drawn wagon. Can it avoid being locked into congested and pollution ways of transporting people and goods3. In Europe most cities are still designed for the old modes of transport. Adaptation to the motor car has involved adding ring roads, one-way systems and parking lots. In the United States, more land is assigned to car use than to housing. Urban sprawl means that life without a car is nest to impossible. Mass use of motor vehicles has also killed or injured millions of people. Other social effects have been blamed on the car such as alienation and aggressive human behaviour.4. A 1993 study by the European Federation for Transport and Environment found that car transport is seven times as costly as rail travel in terms of he external social costs it entails such as congestion, accidents, pollution, loss of cropland and natural habitats, depletion of oil resources, and so on. Yet cars easily surpass trains or buses as a flexible and convenient mode of personal transport. It is unrealistic to expect people to give up private cars in favour of mass transit.5. Technical solutions can reduce the pollution problem and increase the fuel efficiency of engines. But fuel consumption and exhaust emissions depend on which cars are preferred by customers and how they are driven. Many people buy larger cars than they need for daily purposes or waste fuel by driving aggressively. Besides, global car use is increasing at a faster rate than the improvement in emissions and fuel efficiency which technology is now making possible.6. A more likely scenario seems to be a combination of mass transit systems for travel into and around cities. With small "low emission" cars for urban use and larger hybrid or lean burn cars for use elsewhere. Electronically tolled highways might be used to ensure that drivers pay charges geared to actual road use. Better integration of transport systems is also highly desirable-and made more feasible by modern computers. But these are solutions for countries which can afford them. In most developing countries, old cars and old technologies continue to predominate. Transport by horse would not be ______

操作系统主要是对计算机系统中的全部软硬件资源进行管理,以方便用户提高计算机使用效率的一种系统软件。它的主要功能有:处理机管理、存储管理、 (28) 、作业管理、 (29) 。Windows是一个具有图形界面的 (30) 系统软件。UNIX操作系统基本上是采用 (31) 语言编制而成的系统软件。在 (32) 操作系统的控制下,计算机能及时处理由过程控制反馈的信息并作出响应。 28()

A. 用户管
B. 文件管理
C. 中断管
D. I/O管理

第三篇 If the salinity(含盐量) of ocean waters is analyzed, it is round to vary only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation—conversion of liquid water to water vapor. In this manner, the salinity is increased, since the sales stay behind. If this is carried to the extreme, of course, white crystals of salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained. The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by evaporation, or decreased by the addition of fresh water by precipitation or runoff. Normally, in tropical regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas. A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water. In the Weddell Sea, off Antarctica, the densest water in the oceans is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portions of the oceans of the world. What does the passage mainly discuss

A. The elements of salt.
B. The bodies of water of the world.
C. The many forms of ocean life.
D. The salinity of ocean water.

给定节点的关键字序列(F,B,J,G,E,A,I,D,C,H),对它按字母的字典顺序进行排列。采用不同方法,其最终结果相同,但中间结果是不同的。Shell排序的第一趟扫描(步长为5)结果应为 (72) 。冒泡排序(大数下沉)的第一趟起泡的效果是 (73) 。快速排序的第一趟结果是 (74) 。二路归并排序的第一趟结果是 (75) 。 (72)处填()。

A. (B, F, G, J, A, D, I, E, H, C)
B. (B, F, G, J, A, E, D, I, C, H)
C. (A, B, D, C, E, E, I, J, G, H)
D. (C, B, D, A, E, F, I, G, J, H)

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