c++ primer 智能指针

#include<iostream>
using namespace std;


//智能指针
class U_Ptr
{
	friend class Hasptr;
	int *ip;
	size_t use;
	U_Ptr(int *p):ip(p),use(1){}
	~U_Ptr()
	{
		cout<<"u_ptr"<<endl;
		//delete ip;
	}
};


class Hasptr
{
public:
	int *get_ptr() const
	{
		return ptr->ip;
	}
	int get_int() const
	{
		return val;
	}
	void set_ptr(int *p)
	{
		ptr->ip=p;
	}
	void set_ptr(int i)
	{
		val=i;
	}
	int get_ptr_val() const
	{
		return *ptr->ip;
	}
	int set_ptr_val(int val) const
	{
		*ptr->ip=val;
	}
	Hasptr(int *p,int i):ptr(new U_Ptr(p)),val(i)
	{
		cout<<ptr->use<<endl;
	}//hasptr p;int i=40,p=&i


	Hasptr(const Hasptr &orig):ptr(orig.ptr),val(orig.val) //hasptr p1;p1=p,
	{
		++ptr->use;
	}
	Hasptr& operator=(const Hasptr& has)  //int j=2;hasptr q=&j;q=p
	{
		++has.ptr->use;
		if(--ptr->use==0)
			delete ptr;
		ptr=has.ptr;
		val=has.val;
		return *this;
	}


	~Hasptr()
	{
		cout<<"已经释放"<<endl;
		if(--ptr->use==0)
		{
			delete ptr;
		}
	}
private:
	U_Ptr *ptr;
	int val;
};
int main()
{
	int i=40;
	Hasptr p1(&i,40);
	int *j=p1.get_ptr();
	cout<<*j<<endl;
	system("pause");
	return 0;
}