下列对于线性链表的描述中正确的是
A．存储空间不一定是连续，且各元素的存储顺序是任意的
B．存储空间不一定是连续，且前件元素一定存储在后件元素的前面
C．存储空间必须连续，且前件元素一定存储在后件元素的前面
D．存储空间必须连续，且各元素的存储顺序是任意的
参考答案：A
解析： 在链式存储结构中，存储数据的存储空间可以不连续，各数据结点的存储顺序与数据元素之间的逻辑关系可以不一致，数据元素之间的逻辑关系，是由指针域来确定的。由此可见，选项A的描述正确。
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| Nur Memet,a 53-year-old farmer,left his home in Shule County of Xinjiang early Saturday morning. With seven young trees on his bicycle,he joined a one-kilome-ter line of people 1 trees in his village. 2 the days when his grandpa's grandpa was alive,his family has been planting trees every spring. He has continued this tradition(传统) 3 over 30 years. His family is not 4 only one in Shule County with a tree-planting tradition, Shule County,which is near the Taklimakan Desert,gets 5 rainfall(降雨) per year. Each spring when the wind blows, Shule County has has "dust fall" 6 rainfall,with dust floating in the air. In order to fight the wind, the people 7 there have a long history of planting trees. They plant as many trees as they 8 for at least four or five days every March. Nur's house is now 9 by more than 400 trees.Though the road to the house is only three-meter 10 ,trees along the sides of the road are as tall as 20 meters. "When I was even shorter than a sheep,my mother told me again and again we should plant trees every year, " Nur said. | |||
| ( )1. A. planting ( )2. A. Because ( )3. A. for ( )4. A. a ( )5. A. many ( )6. A. next to ( )7. A. visiting ( )8. A. can ( )9. A. damaged ( )10. A. tall | B. cutting B. So B. in B. an B. few B. because of B. living B. must B. surrounded B. high | C. buying C. Since C.during C. / C. little C. nothing but C. moving C. may C. filled C. wide | D. selling D. However D. on D. the D. much D. instead of D. traveling D. need D. broken D. deep |