c++ - 引用在 C++ 中占用内存吗？

Question

我看了很多关于这个问题的文章，从中我了解到引用只是别名，它们不消耗任何内存。编译器用指向变量的地址替换引用。

任何人都可以解释一下下面的例子会发生什么。编译器如何使用引用 ri？

int main()
{  
    int *pi = new int(50);
    int &ri = *pi;
    ri = 30;
    cout << "val = " << ri << " , " << *pi << endl;
}

它给了我输出:

val = 30  ,   30

Answer 1

int *pi = new int(50);

       +----+
pi --> | 50 |
       +----+


int &ri = *pi;

        +----+
pi  --> | 50 |    ri = 50, same as *pi, which is 50
        +----+

ri = 30;      now the contents of what pi points to i.e. *pi is replaced with 30

        +----+
pi  --> | 30 |
        +----+