C++ 복사생성자..

#include <iostream>
 
class Pair {
public:
    int *pa, *pb;
    Pair(int, int);
    Pair(const Pair &);
    ~Pair();
};
 
Pair::Pair(int a, int b): pa(new int(a)), pb(new int(b))
{
    // do nothing
}
 
Pair::Pair(const Pair & obj): Pair(*obj.pa, *obj.pb)
{
    // do nothing
}
 
Pair::~Pair()
{
    delete pa;
    delete pb;
}
 
std::ostream &operator<<(std::ostream &o, const Pair &p)
{
    o << '(' << *p.pa << ", " << *p.pb << ')';
    return o;
}
 
int main()
{
    Pair p(15,16);
    Pair q(p);
    Pair *hp = new Pair(23,42);
 
    std::cout << p << std::endl;
    std::cout << q << std::endl;
    std::cout << *hp << std::endl;
 
    delete hp;
 
    return 0;
}