Question

[!!Correction made to the second code!!]

vector<int> a;
vector<int>*p = &a;

and

vector<int>*b = new vector<int>();

I know that in first scenario, a is on stack and in second b is on heap. But, are there any other differences? Like memory consumed etc.

Answer 1

Yes vector b is allocated on the heap and vector a is on the stack (assuming the code is in the scope of a method) along with a 4 byte pointer also on the stack. Other differences in memory consumed would depend on the memory manager and how it allocates blocks and any internal bookkeeping required for the heap.