copy constructor of a class which has self-pointer to itself in C++?

Question

I wanted to ask that how will we implement a copy constructor of a class which has self pointer to itself as its data member, i want to implement a deep copy,

class City
{
    string name;
    City* parent;
public:
    City(string nam, double dcov);
    City(string nam, double dcov, City* c);
City(const City& obj)

{

    this-> name = obj.name;
// how to assign parent 
parent = new City(??)
}
    ~City();

    void setName(string name1);
    void setDistanceCovered(int dist);
    string getName();
    double getDistanceCovered();
    City* getParent(){return parent;}


};

I am confused that this line // how to assign parent parent = new City(??)will call constructor again instead of deep copy? Regards.

Answer 1

How about

if (obj.parent != NULL)
    parent = new City(*obj.parent)
else
    parent = NULL;

This should work unless you have cycles in the parent hierarchy.