Why doing it with the 'new' keyword?

Question

hello, i am wondering what is the deffirence between instantiating (or creating) an object this way:
Myclass obj(cnstr);
and this way:
Myclass obj = new Myclass(cnstr);
?????
i jus don't get the difference!!

Answer 1

First of all.
Stack is for static memory allocation. Heap is for dynamic memory allocation.
They are the two sections of the memory layout of a process.

Myclass obj(cnstr);
is to allocate an object on the stack

Myclass obj = new Myclass(cnstr);
is to allocate an object on the heap.

as a "for now" rule. think of it this way.
You can use stack if you know how much data needs to be allocated to that object/instance (precisely) before compile time.
Or use heap if you don't know how much data allocation it'll take at run-time (especially if it takes a lot)

PS always 'delete' the memory of the object you allocated 'new' to, otherwise you'll have memory issues with your prog

Answer 2

Thank you Malu for making things clear to me.