神奇的东西

#include <iostream>
using namespace std;


class A
{
public:
A()
{
count = 0;
cout<< "A()"<<endl;
}
// A(A& a)
// {
// cout<< "A(A& a)"<<endl;
// }
~A()
{
count--;
cout<< "~A()  "<<count<<endl;
}


void operator =( A a)
{
cout<< " = "<<endl;
}


int count;
};
A fun()
{
return A();
}


void main()
{
A a1;
a1 = fun();

int k =1;

}

输出：

A()

A()

~A() -1

~A() -1

去掉注释：

A()

A()

~A() -1