Help with linking list

I need some help writing a c++ program using a linking list. This program ask the user to enter the name of an animal, once entered, it tells the user what type of animal it is. For example user enters "cow "and he gets a response "That is a mammal". However if the user enters "cow" and "cow"is not in its library, the user will be prompted to specify the what class of animal it is for example mammal. This information will then be stored in a library for later use. Basically this program gives information and can learn from the user. Any assistance will be greatly appreciated.
Thanks
Ravi ;)