c++ - Allocating a vector vs. a pointer to a vector

Say I have two sets of
code,

std::vectorv1;

and

std::vector
            *pV2 = new
            std::vector(10);

What
is the difference between the two other than the fact that you will have a larger chunk
of memory allocated with the pointer to the vector? Is there an advantage to one vs. the
other?

In my mind, it seems like allocating the
pointer is just more of a hassle because you have to deal with deallocating it
later.

Answer

What is the difference between the two other than
the fact that you will have a larger chunk of memory allocated with the pointer to the
vector?

1. 'will
   have a larger chunk of memory allocated'
   This isn't necessarily
   true! The std::vector might choose a much larger
   default initial size for the internally managed data array
   than 10.


2. 'What is the
   difference between the two'
   The main difference is that the 1st
   one is allocated on the local scopes stack,
   and the 2nd one (usually) goes to
   the heap. Note: The internally managed data array goes to
   the heap anyway!!

To
ensure proper memory management when you really have to use a
std::vector* pointer allocated from the heap, I'd
recommend the use of class="post-tag" title="show questions tagged 'c++'" rel="tag">c++ smart
pointers,
e.g.:

std::unique_ptr
            > pV2(new
            std::vector(10));

For
more details have a look at the documentation of href="http://en.cppreference.com/w/cpp/memory"
rel="nofollow">.