That one's not so obvious. So let's think about this for a second. To sort a list in linear time, would say, I have to look at each element in the list at most a constant number of times.

所以让我们来思考一会,要在线性时间能排序，列表里每个元素最多被使用常数次,不一定是一次，对吧。

麻省理工公开课 - 计算机科学及编程导论课程节选

In my in my area of research, it's common for us to want to process about 100 images a second in order to get real time display. Each image has about a million elements in it. I 've got to process about a half a gig of data a second in order to get anything out of it.

在我们的研究领域内，我们经常要在一秒钟内处理大概,100张图片以获得实时显示,每个图片大概包括了100万像素,因此我必须在1秒内,处理半个G的数据,来获取我想要的。

麻省理工公开课 - 计算机科学及编程导论课程节选