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Does it really matter to you whether your code is going to take 300 years or 900 years to run?
或者900年区别大么？,这个数字的规模才是问题关键所在？
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So this we would want to delete in order for the code not to run the risk of crashing, but let's now see this was made by an excellent teacher out at Stanford University.
我要按顺序删除它，不要冒崩溃的风险,但是这个是由一个来自斯坦福大学的,优秀教师做的。
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I'm thinking about a problem, I'm going to show you an example in a second, first thing I'm going to do is say, what is the thing that's going to change every time I run through the same set of code?
我要解决一个问题，我马上会让大家看一个例子，第一件我要做的事情就是,弄明白每次运行同样的指令集时,每次都会改变的东西是什么？
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That was the kind of thing you saw. Asserts said here are some conditions to test. If they're true, I'm going to let the rest of the code run.
这就是你看到的,断言是一些测试条件,如果他们为真。
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With simple branching, how long is it going to take to run a piece of code?
但是在简单分支程序中，执行一个程序,要多长时间呢？
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Let's run merge sort on it, and then we'll look at the code.
让我们在这个列表上运行归并排序，然后我们在看一下代码。
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OK. All right, let me show you one other tool that I want to use. Which is, I've written that piece of code, I ought to check it. Well, I could just run it, but another useful thing to do is, I'm, especially as I want to debug these things, is to simulate that code.
好，那么，让我给大家讲下,我想用的另外一个工具吧,也就是，我已经写好了这一块代码，我应该去检查检查,那么我可以去运行它,但是特别是当我想要调试代码的时候。
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Pseudo code. Now, you're all linguistic majors, pseudo means false, this sounds like code that ain't going to run, and that's not the intent of the term. When I say pseudo code, what I mean is, I'm going to write a description of the steps, but not in a particular programming language.
伪代码，基于你们都是学语言的，伪代码意味着不正确,这听起来就像是没法运行的代码,这可不是我们学这个的目的，当我说到伪代码的时候,我的意思是要对步骤进行一个描述,而不是某种特定的编程语言。
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Remember last time, I said that there's different kinds of complexity in our code, and I suggested for simple branching programs, the amount of time it takes to run that program is, in essence, bounded by the number of instructions, because you only execute each instruction at most once.
但是这里有个很重要的点,记得上节课，我提过在我们的代码中，有不同种类的复杂度，而且我还说了对于简单的分支程序,运行这种程序需要的总体时间,大体上，是和指令的数目相关的,因为每个指令只会被执行最多一次。
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This code does swap the two values, A and B. However, when I run this program, something happens.
这个代码没有交换那两个值，A和B，但是，当我运行这个程序时，有些事情发生了。
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So the interpreter is simply operating directly on your code at run time.
因此解释器在运行程序的时候,会直接的对你的代码进行操作。
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And you can write your source code in it but to compile something you don't run a command like GCC and then the name of the file, you instead click a button.
你们可以在上面写源代码,如果要编译的话，不用像GCC这样要输入命令，文件名,只需点击按钮就可以了。
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