设栈S和队列Q的初始状态为空，元素按照a、b、c、d、e的次序进入栈S，当一个元素从栈中出来后立即进入队列Q。若队列的输出元素序列是c、d、b、a、e，则元素的出栈J顷序是 (58) ，栈S的容量至少为 (59) 。
（59）处填（）。
A．2
B．3
C．4
D．5
参考答案：B
解析：
[分析]： 本题考查栈和队列的基本概念及运算。
栈是先进后出的线性表，而队列是先进先出的线性表。若队列的输出元素序列为c、 d、b、a、s，则进入队列的元素序列也为c、d、b、a、e，这也是从栈中出来的元素序列。
若元素以a、b、c、d、e的次序进入栈S且得到输出序列c、d、b、a、e，则操作系列为a入栈、b入栈、c入栈、c出栈、d入栈、d出栈、b出栈、a出栈、e入栈、s出栈。第一个出栈的元素为c，则c出栈时元素a和b尚在栈中，如下图所示。
栈S的容量至少为3。
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| These days computer games have become more and more popular in many cities and towns. A lot of small shops along busy 1 have changed into computer game houses in order to get more 2 . These places are always crowded with people. In the computer game houses, people 3 a lot of money matching on the machines. It's 4 for one to beat a computer, but one can do well after trying again and again. People want to 5 when they play computer games. The more they 6 , the more they want to win, and at last they even can't 7 without it. The result is that some people don' t want to 8 , and they play in computer game houses for hours and hours. For school boys, things are 9 . They don't want to have 10 . When school is over, they rush to the computer game houses near their 11 . Some of them can get enough money from their 12 . Some of them are 13 enough to get the money. So they have to steal or rob others' and become 14 . Computer game addiction (上瘾) is a 15 problem in our life. Something has to be done to stop it. | ||||
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