It's looking at the end test. It's looking at the kinds of conditions you're going to put in.

写代码的方法了，也就是通过讨论终结测试,通过讨论放入的条件。

麻省理工公开课 - 计算机科学及编程导论课程节选

Well, break it down into pieces. Suppose x is positive. Does it terminate? Sure. All right?

好，分开来讨论，假设x是整数,程序会终结么？肯定会的对不对？

麻省理工公开课 - 计算机科学及编程导论课程节选