Introduction - If you have any usage issues, please Google them yourself
Create Rodent (rodent): Mouse (mice), Gerbil (sand rat), Hamster (hamster) and other hierarchical structure of a successor. In the base class, provide methods for all Rodent and cover them in the derived class, which according to different types of Rodent take different actions. Create a Rodent array, in which the filling of different types Rodent, then call their base class methods, see what happens. Requested that the definition of a Rodent abstract class.