As I keep moving down, that part gets smaller, it's not always the initial length of the list, and you're right. But if you do the sums, or if you want to think of it this way, if you think about this more generally, it's always on average at least the length of the list.

等等，随着移动，剩下的部分越来越小，并不是初始那么长了，如果你算一算，或者你这么想，你考虑更一般的情况，平均下来至少是列表的长度。

麻省理工公开课 - 计算机科学及编程导论课程节选

In binary search-- ah, there's that wonderful phrase, this is called a version of binary search just like you saw bin-- or bi-section methods, - when we were doing numerical things- in binary search, I need to keep track of the starting point and the ending point of the list I'm looking at.

就是当我们处理数字的时候，所称的二分检索，在二分法搜索中,我需要记录区间的开始点和尾点，初始化的时候就是-,问题输入的开始点和尾点，当我开始做测试的时候,我想要做的就是去取中值点。

麻省理工公开课 - 计算机科学及编程导论课程节选