vector method

* create
* iterator
* add
    * Push the elements into from the back
    * Insert new elements before the element at the specified position.
* change
    * Change the element by index
    * Swap the contents of one container with another container of same type. Sizes may differ.
    * Assign new value to the container by replacing old ones
    * Capacity management, including resize, shrink, and reserve.
* query
    * Get the element at index 
    * Get the first element
    * Get the last element
    * Get the number of elements
    * Get the maximum number of elements
    * Get the size of the storage space currently allocated
    * Get whether the container is empty.
* delete 
    * Pop or remove elements from the back
    * Remove elements from a container from the specified position or range.
    * Remove all the elements of the vector container