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I know this is a simple example, but when you mature as a programmer, one of the first things you should do when you sit down to tackle some problem is write something like this pseudo code.
我知道这是个很简单的例子，但是当你们成长为一名程序员后，当你们碰到问题后第一件事情就是,该写一些类似于,伪代码的东西。
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And we hope that at the end of the class, every time you're confronted with some technical problem, one of your first instincts is going to be, "How do I write the piece of code that's going to help me solve that?"
并且我们希望到了期末，每当你要面对一些,技术问题的时候，你们的本能之一将会是：,“我怎么才能编写一个代码,来帮我解决这问题？“
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And for a couple of reasons, one this is the first P set where we're actually gonna give you code to work from.
由于一些原因，这里是第一个习题集,在此我们提供了一些代码供大家参考。
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If I come into this code, I'm going to check this branch first, if it's not true, ah, there's a return at the end of that branch. If it is true, I do that, and then I've got a second test. If it's true, return I return, otherwise a return.
但是如果我们看看这里,如果我看这段程序,我会先检查这一部分，如果它是假的，啊，这部分分支结尾有一个。
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Well, the first line of code, I'll fix the purple next time around so it's more legible.
第一行代码，我用紫色标记,这样增加了可读性。
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Because there will not be time to look at that code for the first time during the quiz, and figure out what it's doing.
因为在考试中,是没有时间去第一次看代码，并弄懂它的意思的。
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It's okay. So this first line of code, I will get it started but then I'm gonna have you take over and actually instruct Philip what to do here.
第一行代码就从这里开始，接下来我会让你,接管并指导飞利浦。
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This chart, very boring and uninteresting but useful to say there are very well defined rules as to when you're writing code, what operators, like what syntax should get evaluated first.
这个图表，看起来很烦，很无趣，但是它很有用,有非常明确的规定,譬如，当你写代码时，就会涉及操作符的优先级。
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First one, when I write a piece of code, especially code that has branches in it, when I design test cases for that piece of code, I should try and have a specific test case for each possible path through the code.
第一点，当我们写代码的时候，尤其是一些含有分支语句的代码的时候，当我为这些代码,设计测试用例的时候，我应该为每一个可能的程序路径,都设计一个特别的用例。
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So this first line of code, and some of this again we'll be rehashed but at least you can delight in the awkwardness that is this demonstration.
因此，第一行代码，有些地方我们需要重新处理下,但至少看到这次,笨拙的演示你会很高兴。
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OK. So if I look at this code, first of all I'm calling search, it just has one call, so looks like search is constant, except I don't know what happens inside of b search. So I've got to look at b search.
首先调用一下搜索，就一步调用,看起来搜索是固定的，除非我不知道二分搜索的原理，那我们来看看二分搜索吧,所以让我们看看，第一行打印出来的内容。
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So this first little piece of code right here says, ok you give me 2 points, I'll create another 1 of these lists and I'll simply take the x, sorry I shouldn't say x, I'm going to assume it's the x, the x-values are the two points, add them together, just right there, the y-values, add them together and return that list.
好，为了来认识到这一点,让我们来看一个简单的小例子，在你们的课堂手册上，你可以看到我写了一个小程序,它假设我得到了，这些点中的一些，我想对它们做一些操作，例如我想把它们加到一起，那么这里的第一小片，代码的意思是，好给我两个点，我会再创建一个数组。
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OK? And in fact, if you look at the code up here, and it's on your handout, the very first one, x 1, right here- if I could ask you to look at it-- is a piece of code to do it. And I'm less interested in the code than how we're going to analyze it, but let's look at it for a second.
实际上，如果你看看,你们课堂发的材料上面的代码，第一页上的，就是那-,大家请看看实现的这一部分代码,我不太关心,我们会怎么解释这个代码,首先让我们先看看。
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And what it's saying semantically is, using that variable as my placeholder, have it walk through this collection, starting at the first thing, execute that code, then the next thing, execute that code, and so on.
它的语义意思就是，把这个变量应用为我的占位符，用它来遍历这个集合，从第一个元素开始，执行代码，然后下一个元素，再执行代码。
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Well, now I go through code very much like what I did for max val in the first place. I check whether it's 0, et cetera, et cetera.
现在我会捋一遍代码,就像我之前捋maxval函数一样,我会检查它是不是0等等等等。
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The standard library, that first line of code, it's not strictly necessary but any time you use a function, a tool that someone else wrote that lives in that so called library, you do need that include line as we'll see.
标准库函数--第一行代码，严格来说，不是每次都要写的，但是一旦你调用某个别人写，的函数，而这个函数又恰巧位于标准库里面,你就要像我们看到的这样，把它include进去。
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OK.Let's look at the code-- actually, let's test this out first before we do it.
因此我已经添加了，就像Guttag教授做的那样-啊，应该这么说。
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But what looks like this orange block as of now in Scratch, add orange to your so called inventory, well, it's gonna take at least two lines of code in C to actually create the inventory array with this first line and then put something like the word orange inside of it.
就好比Scratch里面橘色的这一块，把“桔子“加到所谓的“清单“里面去,在C语言中至少需要两行代码来实现,第一行代码创建一个货单数组,第二行就需要把“桔子“放进去。
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And in fact, now let me ask those two questions about this piece of code. First question is, for what values of integers-- we're going to assume integers-- but for what values of x does this code terminate? And the second question is, for what values of x does it give me back the right answer?
实际上，让我关于这块代码问两个问题,第一个问题是，对于什么样的整数值，我们会假设是整数,对于x的什么值程序,会最终终止？第二个问题是,对于x的什么值程序,会返回正确答案？
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