所以我试图学习如何使用朋友类来改变私有类成员的值,但是朋友类不能改变主类的值,这是我所做的代码,我是编码世界的新手,请帮帮我:)
#include <iostream>
using namespace std;
class A {
private:
int marks;
public:
show_marks()
{
cout <<marks;
}
set_marks( int num )
{
marks =num;
}
friend class B;
};
class B{
public:
show_A_marks(A teacher, int num){
teacher.marks= num;
}
};
int main(){
A teacher;
teacher.set_marks(10);
teacher.show_marks();
cout <<endl;
B student;
student.show_A_marks(teacher,20);
teacher.show_marks();
}
- 这应该打印:10 20 但正在打印:10 10