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OK. So to do this, we're going to have to do a couple of things. All right, the first one is, what do we mean by input size?
好，为了实现这种方法我们,有些事情要做，第一件事情就是，当我们说到输入的大小的时候代表了什么呢？
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As I said, what we want to do is, we want to count the number of basic steps it takes to compute a computation as a function of input size.
我刚才提到了，我们要建立，一个根据输入大小的方法来计算,一个计算过程需要的时间,建立这个方法需要几步呢？
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These things run for variable amounts of time because they take input, a list of size of some amount.
而这一段的执行时间是可变的,因为它们需要输入一个包含一些元素的列表。
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All right, those pieces of code inherently involved something that does depend on the size of the input, or on the particular input.
好，这些代码,肯定会涉及到一些,与输入的大小相关的东西，或者说与特定输入相关。
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Obviously the algorithm is likely to depend on the size of the input, so this is not a great idea.
很明显这个算法是与我的,输入的大小相关的，因此这不是个好方法。
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And by that, I mean, not how much memory do I need to store the size of the input, it's really how much internal memory do I use up as I go through the computation?
需要占用多少内存,我意思并不是，存储输入需要多少内存,而是当我完成这个？
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Another way of saying it is, if I, for example, 10 increase the size of the input by 10 10 the amount of time increases by 10.
另一种说法就是，例如，我把输入的规模增加0,解决花费的时间也会增加。
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STUDENT: So, how do you come to a conclusion as to which you should use then, if you can determine the size based on solution, or based on input, so how do you decide?
学生：所以，你怎样决定你该用,哪个来算呢？现在如果你可以选择是，基于解决方案的大小，还是基于输入的大小，你应该怎样决定呢？
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It didn't depend on the size of the input.
这和输入的大小是无关的。
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So the running time of the problem where the input is T of size N as expressed here formulaically, T of N, the running time of an algorithm, given an input of size N. You know what?
因此一个输入为N的问题的运行时间,在这儿的公式表示为，如果输入为N，那么此算法的运行时间,是多少呢？
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b OK. In this example I'd use b. All right, as b get-- b is the thing that's changing as I go along here, but it could be things like, how many elements are there in a list if the input is a list, could be how many digits are there in a string if the input's a string, it could be the size of the integer as we go along. All right.?
好，在这个例子里我会用，因为b是一直在变的东西,但是也可能是如下情况：,如果输入是数组的话,变化的就是数组的元素数，如果输入是字符串的话,变化的就是字符串的长度，如果是integer的话,可能就是这个数的大小，对不对？
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