problem_174.js

// Ad-hoc polymorphism
// Allow multiple functions that perform an operation on different
// add(int, int) and add(str, str) would be separately implemented

// Parametric polymorphism
// This allows a function to deal with generics, and therefore on any concrete definition of the generic.
// e.g. A List type in Java, regardless of which objects are in the list

// Subtype polymorphism
// This allows subclass instances to be treated by a function they same way as it would superclass instances
// e.g. Instances of Cat will be operated on a function the same way as instances of it's superclass Animal.