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And so the fact that in this whole slide here, this algorithm for sorting, I'm using the verb sort.
在这个排序算法中,我用到了一个动词排序。
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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。
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Alright, so we can implement any number of algorithms using this thing because the basic mechanism I have here is a comparator.
好了，利用它我们可以实现,很多种算法,因为在此我用到的基本原理是一个比较器。
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Where have we implemented a greedy algorithm, or have been asked to do a greedy algorithm? Well, there are not that many things you guys have been working on this semester.
现在你已经实施了一个贪婪算法,我们在哪里实施了贪婪算法,或者我们那里被要求实施贪婪算法呢？,们这学期不需要用什么功对吧？
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And so one of the things we'll look at today is how can we leverage an algorithm, how can we implement an algorithm that at least at first glance the second time we've now seen it feels so obviously better.
因此，今天我们要学习的一点就是,我们怎样才能影响一个算法，怎样实现一个算法,使你在第二次看它时会觉得,至少比你第一次看到它时更好。
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And we can just extrapolate in a straight line We before saw some examples where I had an algorithm to generate points, and we fit a curve to it, used the curve to predict future points and discovered it was nowhere close.
我们可以干脆用一条直线来描述它,我们之前看到在一些例子中,我用一个算法去生成一些点，然后用一条曲线对它进行拟合，然后用这条曲线来预测未来的点,最后却发现结果完全不对。
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If I'm running a linear algorithm, it'll take one microsecond to complete.
算法会在1微秒内完成，如果是一个平方级的方法。
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Notice here that it's different than the binary search case. We're certainly dividing down, but the combination now actually takes some work. I'll have to actually figure out how to put them back together. And that's a general thing you want to keep in mind when you're thinking about designing a divide and conquer kind of algorithm.
一个分治的例子,注这里，与二分查找所不同的地方,我们肯定是分解了,但是合并的过程还是需要一些工作量的,我会详细说明怎样把它们合并在一起的,当你在考虑设计一个分治算法时,这是你要必须记住的最基本的东西。
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So the first one here is something called insertion sort which amounts to going through the list, taking the first thing that you see and inserting that element into its correct place, - then moving on to the next one, dealing with what element-- whatever element you're given and putting it in its right place.
首先是插入排序,在此算法中，需要遍历整个列表,将你遇到的第一个元素放在其正确的位置，然后移动到下一个元素，继续处理-,不管是什么元素,都将其插入到合适的位置。
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