And when you call a function, one of the things X that happens is whatever your passing in, for instance, X, ; and if this is A, this thing gets copied into A; so at that moment in time of calling increment, I actually have two copies of the same value in memory but they're referred to by different names.

当你调用一个函数，其中发生的一件事情是,不管你输入什么，比如，或者是A，它把这个东西复制到A中;,调用increment的时候，实际上在内存中，有两个同样的值的内存块,但是它们有不同的名字。

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