OK. Binary search is perhaps the simplest of the divide and conquer algorithms, and what does that mean? It says, in order to solve a problem, cut it down to a smaller problem and try and solve that one.

好了，二分搜索也许是,最简单的分治算法，这意味着什么？,也就是说，为了解决一个问题,把它切割成小的问题,然后再来一个个解决。

麻省理工公开课 - 计算机科学及编程导论课程节选

All right? I don't care what's in there, but just assume that's my list. And just to remind you, on your handout, and there it is on the screen, I'm going to bring it back up, there's the little binary search algorithm.

好，我不管列表里是什么，就假定那是一个列表,要提醒你们的是,在你们的讲义上和屏幕上，有一个简单的二分查找算法。

麻省理工公开课 - 计算机科学及编程导论课程节选

OK. At the end of the lecture last time, I also showed you an example of binary search.

好的，在上次课程的最后，我也给你们看了一个二分查找的例子。

麻省理工公开课 - 计算机科学及编程导论课程节选

The instant unlike binary search, where each instance was separate, here the instances overlap.

这个例子不像搜索二进制数，每个例子是独立的，这里的例子是相互重叠的。

麻省理工公开课 - 计算机科学及编程导论课程节选

OK. So, what do I want you to take away from this? This idea of binary search is going to be a really powerful tool. And it has this property again, of chopping things into pieces.

从这里学到些什么？二分查找的思想,是一个非常有用的工具,我重复一遍，把问题拆成几部分来解决,那事实上，这里的增长率是多少？

麻省理工公开课 - 计算机科学及编程导论课程节选

Again. Basic premise of binary search, or at least we set it up was, imagine I have a sorted list of elements. We get, in a second, to how we're going to get them sorted, and I want to know, is a particular element in that list..

好，二分查找的基本前提，或者是我们建立二分查找的基础,我们已经有了一个排好序的元素列表，我们就需要知道如何来快速的排序,如何从列表中找到特定的元素。

麻省理工公开课 - 计算机科学及编程导论课程节选

Now, one of the questions we could still ask is, right, we've got binary search, which has got this nice log behavior.

目前，还有一个问题我们仍然要问的是，对，我们已经学了二分查找，有着非常好的log级别的行为。

麻省理工公开课 - 计算机科学及编程导论课程节选

Let's pull together what this algorithm actually does. If I generalize binary search, here's what I'm going to stake that this thing does.

总结下二分查找法,下面列举几点它的操作，首先，找中点。

麻省理工公开课 - 计算机科学及编程导论课程节选

I'm narrowing it down. It's getting a little silly but you know I'm going to really be persistent and just follow the rules here of binary search, rather than jumping to conclusions.

按照二分法的规则来做的,而不是直接得出某种结论,很明显这儿我的目的是什么？,显示这两个相同的东西。

麻省理工公开课 - 计算机科学及编程导论课程节选

Now, as I do this, I'm going to use binary search.

现在当我做这项工作的时候，我会用到二分搜索法。

麻省理工公开课 - 计算机科学及编程导论课程节选

OK. That's the basic idea of binary search.

好了，这就是二分查找的基本思想。

麻省理工公开课 - 计算机科学及编程导论课程节选