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You'll also notice that this thing goes through the entire list, even if the list is sorted before it gets partway through.
你也能注意到，它始终会遍历列表,甚至列表在排序之前,就是有序的也是这样。
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I haven't said how I'm going to get those sorted lists, but imagine I had two sorted lists like that.
我还没有说明我怎么才能得到已排序的列表,但是想像一下我现在已经有,两个已排序好序的列表了。
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If it was an unordered list, we were basically stuck with linear search. Got to walk through the whole list to see if the thing is there.
如果是一个未排序的列表,基本上我们就只能使用线性搜索了,通过遍历整个列表来查看。
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Where those pieces, I would do the same thing with, I would divide them up into smaller chunks, and sort those. Is that going to give me a more efficient algorithm?
合并起来，而那些小列表,我又会把他们拆成更小的列表,再排序，这会给我,一个更高效的算法么？
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Merge sort takes this idea of divide and conquer, and it does the following: it says let's divide the list in half.
归并排序以如下的步骤使用了分治思想：,把列表分成两半：,下面就是分治。
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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。
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Well let's see. My fall back is, I could just do linear search, walk down the list one at a time, just comparing those things. OK. So that's sort of my base. But what if I wanted, you know, how do I want to get to that sorted list? All right?
我只能做线性搜索了,一次遍历一遍列表，一个一个比较，但如果我想要,那怎样得到有序的列表呢？,现在的一个问题是，我们排序之前？
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So to just preface what we're going to do next time, what would happen if I wanted to do sort, and rather than in sorting the entire list at once, I broke it into pieces, and sorted the pieces, and then just figured out a very efficient way to bring those two pieces and merge them back together again?
所以为了引导下一次,我们要讲的内容,如果我想做排序,而且不是一次吧整个列表排完,会发生什么，我把它拆成小的列表,然后把各个小列表排序,接着用高效的方法再把小的列表？
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