类和类之间访问私有变量

#include<iostream>
using namespace std;
class Building;
class Gooddey{

public:
	friend  Building;
	Gooddey();
	void visit();
	Building *building;
};
class Building{
	friend	class Gooddey;
public:
	Building(){
		this->age = 10;
		this->ac = 20;
	}
public:
	int age ;
private:
	int ac ;
};
Gooddey::Gooddey(){
	building = new Building;
}
void Gooddey::visit(){
	cout << building->age << endl;
	cout << building->ac << endl;
}
void test(){
	Gooddey p;
	p.visit();
}
int main(){
	test();
}