Since vector elements are stored contiguously, I guess it may not have the same address after some push_back's , because the initial allocated space could not suffice.

I'm working on a code where I need a reference to an element in a vector, like:

int main(){
    vector<int> v;
    v.push_back(1);
    int *ptr = &v[0];
    for(int i=2; i<100; i++)
        v.push_back(i);
    cout << *ptr << endl; //?
    return 0;
}

But it's not necessarily true that ptr contains a reference to v[0], right? How would be a good way to guarantee it?

My first idea would be to use a vector of pointers and dynamic allocation. I'm wondering if there's an easier way to do that?

PS.: Actually I'm using a vector of a class instead of int, but I think the issues are the same.