Pointers:
Things to remember
Pointers are NOT integers.
Always to test whether or not memory allocation requests are successful.
Only memory that has been allocated using new (or the related routines) should be freed using delete operator.
To pass a parameter by variable, specify this parameter that is a pointer, use a pointer to pointer.
Always cast the NULL pointer when it is passed as an actual parameter.
Do not declare pointer as a global variable.