OK. So to do this, we need a little more abstract way of talking about efficiency, and so, the question is, how do we think about efficiency? Typically there's two things we want to measure.

好，为了达到这个目的,我们需要用一种有点，抽象的方式去讨论效率，这衍生出来,一个问题，我们该怎么去认识效率？,主要来说我们有两个要量化的东西。

麻省理工公开课 - 计算机科学及编程导论课程节选