NULL pointer is the same as deallocating it?

Question

I was working on a piece of code and I was attacked by a doubt: What happens to the memory allocated to a pointer if I assign NULL to that pointer?

For instance:

Answer 1

Variables stored on the stack, are the local variables of each function, e.g. int big[10]; Variables stored on the heap, are the variables which you initiated using explicit memory allocation routines such as malloc(), calloc(), new(), etc.

Variables stored on the stack have a lifetime that is equal to the lifetime of the current stack frame. In English, when the function returns, you can no longer assume that the variables hold what you expect them to hold. That's why its a classic mistake to return a variable that was declared local in a function.