@danieldsouza23 Hashes associate arbitrary keys to arbitrary values, vectors associate indices (size_t) to arbitrary values. As you can see vector is a special hash, hit up an algorithms course/book to learn more about these two. In this special case even the arbitrary values are
ints, so that may be confusing as well.
Check constructor 2) on http://en.cppreference.com/w/cpp/container/vector/vector for meaning of