classes, pointers, vectors, and memory allocation

mosfets_at_gmail.com
Date: 02/06/05 

Date: 5 Feb 2005 23:37:02 -0800

Hi,

I'm having a little trouble figuring out the difference in terms of
memory allocation between:

class person_info;

class A {

private:
    vector<person_info> list;
};

class B {

private:
    vector<person_info*> list;
};

int func1() {

A* ptr1 = new A();
B* ptr2 = new B();

person_info info_stack;
person_info* info_heap = new person_info();
}

ptr1 and ptr2 will be dynamically allocated in the heap, but when I add
info_stack to ptr1's vector list, info_stack will be copied into the
heap??? Or will info_stack still reside in the stack? If it is added
into the heap, does A's memory get enlarged as a whole chunk? If there
is not enough space for the whole chunk, will A get copied into another
chunk in the heap big enough to fit it?
What happens when I exit func1 and info_stack gets destroyed, what will
happen to the info_stack I put into the vector in ptr1? Can I still
access it and keep using it?

When i add info_heap to ptr2's vector list, will the memory of B in the
heap be enlarged as a whole chunk?

Sorry for so many questions, but I've been really confused about this
for a while.

Thanks for any help, and for reading this!
John G

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