下面回答第二题，不要像第一题那样花那么多时间。

To answer the second question, don't take as much time as you took for the first question.

youdao

所以，我们可以像之前我们做的那样解这道题。

So then, we can do it the same way we did here.

youdao

两次练习测验中,都有一道题是关于变量替换的,感觉这是很重要的那样。

There is one change of variable problem on each of the two practice exams to give you a feeling for what's realistic.

youdao

3 So here what I'm doing is 17 divided by 13, but because of this parenthetical, , -- because of that parenthetical -- that has nothing to do with math; -- this is a programming language thing -- that is a casting operation.

所以这里我要做的是用17除以，但因为这样的题外话，因为那样的题外话-,还是没有做完这个数学题;,这是一个编程语言的东西-,那是一个计算操作。

哈佛公开课 - 计算机科学课程节选