Vectors are a kind of sequence containers. As such, their elements are ordered following a strict linear sequence.
Vector containers are implemented as dynamic arrays; Just as regular arrays, vector containers have their elements stored in contiguous storage locations, which means that their elements can be accessed not only using iterators but also using offsets on regular pointers to elements.
But unlike regular arrays, storage in vectors is handled automatically, allowing it to be expanded and contracted as needed.
Vectors are good at:
* Accessing individual elements by their position index (constant time).
* Iterating over the elements in any order (linear time).
* Add and remove elements from its end (constant amortized time).
Compared to the other base standard sequence containers (deques and lists), vectors are generally the most efficient in time for accessing elements
and to add or remove elements from the end of the sequence. For operations that involve inserting or removing elements at positions other than the end, they perform worse than deques and lists, and have less consistent iterators and references than lists.