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drawbacks of using multilevel two cars, but consider them subclasses
inheritance in an OOP application. of a superclass that defines these
3. Provide a simple, real-world operations. Also, if you imagine a super
example of multilevel inheritance class named “Animal.” As explained in Chapter Four: Object oriented programming with C++
involving a base class, a derived the previous paragraph in inheritance,
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class, and a further derived class, this class might have a method called
and explain how methods and “makeSound()”. Coming to subclasses
attributes are inherited and extended like “Dog” and “Cat” that inherit
at each level? properties from “Animal.”, both “Dog”
and “Cat” inherit the “makeSound()”
method. This reflects Polymorphism
Polymorphism especially when “makeSound()” behave
Polymorphism is an important concept differently for Dog class and for Cat
in Object-Oriented Programming that class. The “makeSound()” on a “Dog”
allows objects from various classes object when it is called, it might bark,
to be viewed as members of the while calling “makeSound()” method on
same superclass. It allows a single a “Cat” object might produce a meow.
interface to represent various sorts of
objects, increasing flexibility and code (a) Roles of polymorphism
reusability. Polymorphism enables a (i) Code reusability: Polymorphism
same method name to perform different makes code reuse possible by giving
actions depending on the type of object classes the ability to implement a
it is called on. common interface. In other words, a
single piece of code can interact with
Example of polymorphism in real world is multiple objects, which eliminates
when you consider parents and children. duplication and encourages effective
The human body can be viewed as an code reuse.
object that has properties and methods.
Examples include private properties (ii) Flexibility and adaptability: Code
like the brain, heart, liver, stomach and can be written in a more flexible
lungs, as well as public properties like and adaptive manner thanks to
the eyes, ears, fingers, head, hair and polymorphism. Code can handle
legs. Another simple example is when several object types without knowing
you reflect someone who understands their unique class by programming
how to drive can get into and drive to an interface instead of specific
most cars since they have key traits implementations. As a result, the
such as a steering wheel, a gear lever, code is more adaptable and able to
and clutch, brake, and accelerator pedals handle a larger variety of situations.
that the driver is familiar with. There (iii) Simplifies code design:
may be many differences between any Polymorphism makes code design

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