I'm simply saying swap X with Y, but this 2 won't work, because where are X and Y defined?

我只简单地说交换X和Y，但是这两行不起作用，因为X和Y是在哪里定义的呢？

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Well, simply with the * notation at least on the way in when you declare the function called swap, you simply say this is not going to take an int and another int because that's useless.

好的，简单说，当你声明一个函数调用swap函数时,使用*符号，你可以简单说，这不能使用一个int数和另外一个int数,因为那是无效的。

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