But the things we were trying to stress were that it's an important design decision when you are coming up with a piece of code, as to what kind of efficiency your code has.

但是我们这里要强调的是,当你写代码的时候,决定你的代码的效率的很重要的事情，就是你的设计决定。

麻省理工公开课 - 计算机科学及编程导论课程节选