Programming and Graphics

146 Introduction to C++ Programming and Graphics

The following code introduces a new pointer and evaluates its content:

#include <iostream>

using namespace std;

int main()

{

int * memad = new int;

cout << memad << endl;

cout << *memad << endl;

return 0;

}

The output of the code is:

0xbff1b08c

0

which shows that the memory content is zero. In the same spirit, we can write:

double * pnt = new double;

cin >> *pnt;

which evaluates the memory content. Note that we do not have to introduce a
name for the variable contained in the memory slot addressed by the pointer,
and we simply use*pnt.

To free the memory cell, we delete the pointerpnameusing:

delete pname;

It is highly recommended that the value of a deleted pointer be reset to zero.
When the value of zero is assigned to a pointer, the pointer becomesnull, that
is, it points to nothing.

The following code contained in the filepointerfree.cc introduces and
immediately deletes a new pointer:

#include <iostream>

using namespace std;

int main()

{

int * memad = new int;

delete memad;

memad=0;

cout<<*memad<<endl;