问题 单项选择题

栈的运算特点是后进先出。元素a、b、c、d依次入栈,则不能得到的出栈序列是______。

A.a b c d

B.c a b d

C.d c b a

D.b c d a

答案

参考答案:B

解析: 首先可用得到出栈序列dcba,如果每个元素入栈后即出栈,则可得abcd,若c位于栈顶,而ab在栈中,则可得cbad,但不能得到cabd。

单项选择题 案例分析题
完形填空

Several years ago, well-known writer and editor Norman Cousins became very ill. His body ached and he felt constantly tired. It was difficult for him to even __21__ around. His doctor told him that he would lose the ability to move and eventually die from the disease. He was told he had only a 1 in 500 chance of survival.

Despite the diagnosis(诊断), Cousins was __22__ to overcome the disease and survive. He had always been interested in medicine and had read a book, which discussed the idea of how body chemistry and health can be damaged by emotional stress and negative __23__. The book made Cousins think about the possible __24__ of positive attitudes and emotions. He thought, “Is it possible that love, hope, faith, laughter, confidence, and the __25__ to 1ive have positive treatment value?”

He decided to concentrate on positive emotions as a way to treat some of the symptoms of his disease. In addition to his traditional medical treatment, he tried to put himself in situations that would __26__ positive emotions. “Laugh therapy” became part of his treatment. He __27__ time each day for watching comedy films, reading humorous books, and doing other activities that would draw out _28__ emotions. Within eight days of starting his ‘‘laugh therapy” program his pain began to __29__ and he was able to sleep more easily. He was able to return to work in a few months’ time and _30__ reached complete recovery after a few years.

21. A. run                    B. pass                         C. move                              D. travel

22. A. able                    B. determined              C. willing                               D. positive

23. A. attitudes             B. beliefs                      C. goals                              D. positions

24. A. shortcoming        B. harm                        C. benefit                                   D. interest

25. A. emotion                     B. pain                        C. fear                                D. will

26. A. bring about         B. set about                  C. put up                             D. make up

27. A. afforded                B. appointed                 C. offered                           D. arranged

28. A. positive                     B. approving                 C. strong                             D. mixed

29. A. escape                B. decrease                   C. shrink                             D. end

30. A. generally            B. especially                 C. actually                           D. presently