C++ - 类内部private和protected访问权限问题

class A
{
public:
A()
{
m_data = 0;
}
void func()
{
A a;
a.m_data = 1024; // 注意：访问a对象的private成员
std::cout << a.m_data << std::endl;
}
protected:
private:
int m_data;
};

int main()
{
A aobj;
aobj.func(); // 1024

return 0;
}