Question

I am writing a heap data structure in C. Theres one thing that I can’t decide on. I am implementing it as an array. The way it works, is that function “insert” takes a pointer to some data and copies all bytes of that data, pointed to, into the array, is that a good approach? Or should I just store the pointer itself, the function was called with?

Answer 1

Well, you have to consider that the memory pointed to will probably be changed or become invalid, for example when it’s a variable on the stack. So in most cases, it would not be a good idea to just store the pointer.
If you must have a function insert() there is no way around copying the memory – although this is slow. Best is to use memcpy(), because this is still the fastest function.

Heaps are usually designed a bit differently: You have a function malloc(int size) that you call to retrieve a pointer to a memory area of desired size. There you can store whatever you need it for.