自学C++半个月遇到的问题求解，有偿

Question

自学 C++半个月，跟着B站黑马程序员的课程，在类函数作友元时遇到了一个问题（第36行），代码的主要思路是跟着视频敲的

#include <iostream>
#include <string>
using namespace std;


class Building
{
    friend void GoodGay::visit();             //此处已经声明了GoodGay::visit()作友元
public:

    string m_sittingroom;
    Building()
    {
        m_sittingroom = "客厅";
        m_bedroom = "卧室";

    }
private:
    string m_bedroom;

};

class GoodGay
{
public:
    GoodGay()
    {
        building = new Building;

    }
    Building* building;

    void visit()
    {
        cout << building->m_sittingroom << endl;  
        cout << building->m_bedroom << endl;    //编译器在m_bedroom这里报错了，可是前面已经声明了visit()的友元地位


    }

};

int main()
{

    GoodGay gg;
    gg.visit();


}

Answer 1

#include <iostream>
#include <string>
using namespace std;

class Building;

class GoodGay
{
public:
    GoodGay();
    Building* building;
 
    void visit();

 
};

class Building
{
    friend void GoodGay::visit();             //此处已经声明了GoodGay::visit()作友元
public:
 
    string m_sittingroom;
    Building()
    {
        m_sittingroom = "客厅";
        m_bedroom = "卧室";
 
    }
private:
    string m_bedroom;
 
};
 
GoodGay::GoodGay()
{
    building = new Building;

}
 
void GoodGay::visit()
{
    cout << building->m_sittingroom << endl;  
    cout << building->m_bedroom << endl;    //编译器在m_bedroom这里报错了，可是前面已经声明了visit()的友元地位


}
    
int main()
{
 
    GoodGay gg;
    gg.visit();
 
 
}