友元函数用来访问类的非公有成员。友元函数不是类的成员函数。
What is a friend function?
A friend function is used for accessing the non-public members of a class. A friend function is a non member function of a class.
友元函数用来访问类的非公有成员。友元函数不是类的成员函数。
What is a friend function?
A friend function is used for accessing the non-public members of a class. A friend function is a non member function of a class.