未知题型
下面程序有注释的语句中，错误的语句是( )。 #include ＜iostream＞ using namespace std； class A{ int a； public： void show A(){cout＜＜'this is A!'；} }； class B：public A{ int b； public： void showB(){cout＜＜'this is B!'；} }； void main(){ A ia，*piA； B ib，*piB； piA=&ia； //第一个测试语句 piA=&ib； //第二个测试语句 piB=&ia； //第三个测试语句 piB=&ib； //第四个测试语句 }
D.第四个测试语句
- A.第一个测试语句
B.第二个测试语句
C.第三个测试语句
【参考答案】
C
解析：派生类的指针不能指向基类。
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未知题型
All types of stress study, whether under laboratory or real-life situations, study mechanisms for increasing the arousal level of the brain.The brain blood flow studies show that reciting the days of the week and months of the year increases blood flow in appropriate areas, whereas problem solving which demands intense concentration of a reasoning type produces much larger changes in the distribution of blood in the brain.Between these basic studies of brain function and real-life situations there is still a considerable gap, but reasonable deduction seems possible to try and understand what happens to the brain. Life consists of a series of events which may be related to work or to our so-called leisure timE.Work may be relatively automatic--as with typing, for instancE.It requires intense concentration and repetition during the learning phase to establish a pattern in the brain. Then the typist's fingers automatically move to hit the appropriate keys as she reads the words on the copy.However, when she gets tired she makes mistakes much more frequently. To overcome this she has to raise her level of arousal and concentration but beyond a certain point the automatic is lost and thinking about hitting the keys leads to more mistakes.Other jobs involve intense concentration such as holding bottles of wine up to a strong light and turning them upside down to look for particles of dirt falling down. This sounds quite easy but experience teaches that workers can do this for only about thirty minutes before they start making a mistakE.This is partly because the number of occasions with dirt in the bottle is low and the arousal level, therefore, fails. Scientists have shown that devices to raise arousal level will increase the accuracy of looking for relatively rare events. A recent study of the effect of loss of sheep in young doctors showed that in tests involving a challenge to their medical judgment when short of sleep they raised their arousal level and became better at tests of grammatical reasoning as well.According to the brain flow studies, problem solving ______.A.increases blood flow in some areas of the brain.B.causes changes in the distribution of blood in the brain.C.demands intense concentration of blood in certain areasD.is based on the ability to recite the time
A.B.
C.
D.
E.
According
F.
A.increases
G.
B.causes
H.
C.demands
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未知题型
A 'knockout' is arranged ______.A.to keep the price in the auction room lowB.to allow one dealer only to make a profitC.to increase the auctioneer's profitD.to help the auctioneer
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未知题型
Whenever two or more unusual traits or situations are found in the same place, it is tempting to look for more than a coincidental relationship between them. The high Himalayas and the Tibetan plateau certainly have extraordinary physical characteristics, and the cultures which are found there are also unusual, though not uniquE.However, there is no intention of adopting Montesquieu's view of climate and soil as cultural determinants. The ecology of a region merely poses some of the problems faced by the inhabitants of the region, and while the problems facing a culture are important to its development, they do not determine it.The appearance of the Himalayas during the late Tertiary Period and the accompanying further raising of the previously established rages had a marked effect on the climate of the region. Primarily, of course, it blocked the Indian monsoon (季风) from reaching Central Asia at all. Secondarily, air and moisture from other directions were also reduceD.Prior to the raising of the Himalayas, the land now forming the Tibetan uplands had a dry continental climate with vegetation and animal life similar to that of the rest of the region on the same parallel, but somewhat different than that of the areas farther north, which were already drier. With the coming of the Himalayas and the relatively sudden drying out of the region, there was a severe thinning out of the animal and plant population. The ensuing incomplete Pleistocene glaciations (冰蚀) had a further thinning effect, but significantly did not wipe out life in the areA.Thus after the end of the glaciations there were only a few varieties of life extant from the original continental species. Isolated by the Kunlun range from the Tarim basin and Turfan depression, species which had already adapted to the dry steppe climate, and would otherwise have been expected to flourish in Tibet, the remaining native fauna and flora (动植物群) multiplieD.Armand describes the Tibetan fauna as not having great variety, but being 'striking' in the abundance of the particular species that are present. The plant life is similarly limited in variety, with some observers finding no more than seventy varieties of plants in even the relatively fertile Eastern Tibetan valleys, with fewer than ten food crops. Tibetan 'tea' is a major staple, perhaps replacing the unavailable vegetables.The difficulties of living in an environment at once dry and cold, and populated with species more usually found in more hospitable climates, are great. These difficulties may well have influenced the unusual polyandrous (一妻多夫的) societies typical of the region. Lattimore sees the maintenance of multiple-husband households as being preserved from earlier forms by the harsh conditions of the Tibetan uplands, which permitted no experimentation and 'froze' the cultures which came therE.Kawakita, on the other hand, sees the polyandry as a way of easily permitting the best householder to become the head husband regardless oF.agE.His detailed studies of the Bhotea village of Tsumje do seem to support this idea of polyandry as a method of talent mobility is a situation where even the best talent is barely enough for survival.In sum, though arguments can be made that a pre-existing polyandrous system was strengthened and preserved (insofar as it has been) by the rigors of the land, it would certainly be an overstatement to lay causative factors of any stronger nature to the ecological influences in this casE.What are the 'unusual traits or situations' referred to in the first sentence?A.Patterns of animal and plant growth.B.Food and food preparation patterns of the upland Tibetans.C.Social and familial organization of typical Tibetan society.D.All of the abovE.
A.B.
C.
D.
E.
What
F.Patterns
G.
B.Food
H.
C.Social
I.
D.All
