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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