And he walks out into the farmyard and he observes 20 heads and 56 legs.

这个农场主有一群猪--这是漫长的一天,一群猪和一群鸡。

麻省理工公开课 - 计算机科学及编程导论课程节选

You could say, I could have zero chickens and 20 pigs, does that work? I've got one chicken and nineteen pigs, does that work?

为什么简单列举出所有可能的情况,再一个来检验？你可能会说,我可以有0只鸡和20只猪，这能行吗？

麻省理工公开课 - 计算机科学及编程导论课程节选

This means there is no more chicken and egg.

这意味着不再有单个的鸡和蛋了。

麻省理工公开课 - 固态化学导论课程节选

And the question is, so how many pigs does he have, and how many chickens does he have? Wow. What a deep problem, right? But you're going to see why we're going to use this in a second. So you know how to solve this, this is a fifth-grade problem, right?

为了避免歧义，这些猪和鸡都是健全的,现在问题是它到底有多少只猪和鸡呢？,多深刻的一个问题啊，对吗？,但是你将要看到的是,我们为什么要举这个例子,你知道如何解答这个问题？

麻省理工公开课 - 计算机科学及编程导论课程节选

System of linear equations. What are the equations here? Well, I could say, you know, the number of pigs plus the number of 20 chickens equals 20, right? Because we've got 20 heads. And then what else do I have?

如何解决这个问题呢？,用线性方程式的办法来解决，等式是什么呢？你应该知道,猪的数量加鸡的数量等于,对吧？因为我们有20个头？

麻省理工公开课 - 计算机科学及编程导论课程节选

I've got two chickens and eighteen pigs, you get the idea.

我有1只鸡和19只猪，这能行吗？,我有2只鸡和18只猪。

麻省理工公开课 - 计算机科学及编程导论课程节选

Knowing that, I'm going to say, OK, how many pigs are there, well that's just how we're, however many I had total, minus that amount, and then I can see, how many legs does that give, and then I can check, that the number of legs that I would get for that solution, is it even equal to the number of legs I started with, ah! Interesting. A return.

它将给我返回头的总数，知道了这些之后我可以说好了,有多少猪呢，无论有多少组鸡的数目，我只要用总数减去那个值,之后我就可以知道一共有多少条腿,然后再把这个值和题目中的腿数相比较，看它是否等于一开始的腿数,啊！真有趣，有一个返回值。

麻省理工公开课 - 计算机科学及编程导论课程节选