C++: daughter-class of std::vector

I've been reading the namespace of std::vector trying to make a daughter class, mainly for experimental reasons. I know it's dangerous and easy to circumvent.

Now I'm facing a problem with the type template. For example, if I call the function input() inside a new function, I would need to pass the type identifier "value_type" (or _Tp) which is defined in vector. That typedef however does not make it to the class vector. How can I include and properly use that template from class Vector?