问题 单项选择题

在虚拟页式存储管理系统中,LRU算法是指( )。

A.最早进入内存的页面先被淘汰

B.近期最长时间以来没被访问的页面先被淘汰

C.近期被访问次数最少的页面先被淘汰

D.以后再也不用的页面先被淘汰

答案

参考答案:B

解析: 用来选择被淘汰页面的算法称做页面淘汰算法。页面淘汰算法有以下几种:最佳淘汰算法(OPT);先进先出淘汰算法(FIFO):最近最久未使用淘汰算法(LRU)和最近最少使用淘汰算法(LFU)。 LRU算法淘汰最后一次访问时距当前时间间隔最长的页面。其出发点是用最近的过去估计最近的将来,即一个已在内存的页面,如果在本次缺页中断前的最近一段时间内,未被使用的时间最长,那么将来它很可能不再被使用,故应淘汰。

阅读理解

Argentina in the late nineteenth century was an exciting place. Around 1870, it was experiencing an economic(经济的)boom, and the capital, Buenos Aires, attracted many people. Farmers, as well as a flood of foreigners from Spain and Italy, came to Buenos Aires seeking jobs. These jobs didn′t pay well, and the people felt lonely and disappointed with their new life in the city. As the unhappy newcomers mixed together in the poor parts of the city, the dance known an the tango(探戈舞)came into being

At the beginning the tango was a dance of the lower classes. It was danced in the bars and streets. At that time there many fewer women than men, so if a man didn′t want to be left out, his only choice was to dance with another man so that he could attract the attention of the few available women. Gradually, the dance spread into the upper classes of Argentinean society and became more respectable.

In Europe at this time, strong interest in dance from around the world was beginning

The interest in international dance was especially evident in Paris. Every kind of dance from ballet(芭蕾舞)to belly dancing could be found on the stages of the Paris theaters of the Paris theaters. After tango dances from Argentina arrive in Europe, they began to draw the interest of the public an they performed their exiting dance in cafes, Though not everyone approved of the new dance, saying it was a little too shocking, the dance did find enough supporters to make it popular.

The popularity(流行)Of the tango continued to grow in many other parts of the world. Soldiers who returned to the United States from World War I brought the tango to North America, It reached Japan in 1926, and in 2003 the Argentinean embassy in Seoul hired a local tango dancer to act an a kind of dance ambassador, and promote tango dancing throughout South Korea.

小题1:The origin of the tango is associated with

A Belly dances B. American soldiers

C. Spanish city D. the capital of Argentina

小题2: Which of the following is true about the tango?

A.It was created by foreigners from Spain and Italy.

B.People of the upper classes loved the tango most

C.It was often danced by two male in the beginning

D.A dancer in Seoul became the Argentinean ambassador.小题3:Before World War I, the tango spread to 

A.America

B.Japan

C.France

D.South Korea小题4:What can be the best title for the text?

A.How to Dance the Tango

B.The History of the Tango

C.How to Promote the Tango

D.The Modern Tango Boom

单项选择题