C++ deleting pointers

Question

I have a program that contains a doctor class, and each Doctor object has a linked list of "Patients". These patients are created using the following line of code

Patient * patient = new Patient(string firstname, string ailment);

And this patient is then added to a Doctor's linked list. There is a pointer in the Doctor class that is used to point to and iterate through the list and get each patient. When I want to delete these patients, I have to start at the beginning of my list and iterate through each one. My question is, can I delete eacg patient by simply calling their destructors as I iterate through them?

Patient::~Patient(){

}

or do I need to actually call delete on the pointer as it points each employee?

Answer 1

You call delete to delete things. delete will, in turn, result in the object's destructor being called.

Calling the destructor of a class directly is supported by C++, and is in fact useful in some rare scenarios, but it does not actually deallocate the memory. This is not what you want to do here.

Answer 2

First, new returns a pointer, so I guess you mean Patient* patient = ... .

That aside, yes, you'll need to call delete on everything you allocate with new and the destructor will be called.

OR (drumroll) use a std::unique_ptr instead. And I hope when you say you have a list of patients, you mean you have a std::list of patients.

Answer 3

调用delete实际上会调用该对象的析构函数。

Answer 4

Since you are dynamically allocating the memory for each Patient object (should be Patient* patient tho...) you need to manually deallocate each one as well...

Check out this wiki page for more info.

Answer 5

As far as I know you have to call delete on each pointer individually. Deleting a pointer to Patient from within the Patient destructor seems to violate the purpose of using classes (ie they are self contained and don't have access to the outside world).