One of the things you should begin to do, is to recognize what identifies those classes of algorithms, so you can map your problems into those ranges.

你们现在开始要做的事情之一，就是要学会辨别这些算法,这样你就能为你的问题，选择对应种类的算法了。

麻省理工公开课 - 计算机科学及编程导论课程节选