🟣 OOP · Lesson 47

Polymorphism in C++

What is Polymorphism in C++?

Polymorphism in C++
Polymorphism means one name with many forms. C++ supports compile-time polymorphism through overloading and run-time polymorphism through virtual functions.

Level
🟣 Object-Oriented Programming

Example File
polymorphism.cpp

Main Focus
Concept + syntax + practical C++ program

Why should you learn this?

It helps you write correct and readable C++ programs.
It is used repeatedly in school practicals, projects and competitive programming.
It builds the base for advanced topics such as OOP, STL and data structures.

Important Terms

Term	Meaning / Use
compile-time polymorphism	Compile-time polymorphism used in Polymorphism in C++ programming.
run-time polymorphism	Run-time polymorphism used in Polymorphism in C++ programming.
overloading	Overloading used in Polymorphism in C++ programming.
overriding	Overriding used in Polymorphism in C++ programming.

Syntax / Pattern

Same function name behaves differently depending on context.

Example Program

#include <iostream>
using namespace std;
class Print{
public:
    void show(int x){ cout << x; }
    void show(string s){ cout << s; }
};
int main(){ Print p; p.show("C++"); }

Expected Output

C++

Program Explanation

show() is overloaded with int and string parameters.
Compiler selects correct function at compile time.

Exam Tip: In C++ practical answers, write the logic first, then the program, then expected output. For theory, always include one suitable example.

Where will you use it?

flexible APIs
OOP design
reusable interfaces

Common Mistakes

Confusing overloading and overriding.
Expecting return type alone to create polymorphism.

Practice Tasks

Give examples of both types of polymorphism.
Overload area function.

Summary

Polymorphism in C++ is an important C++ topic. Learn the definition, understand the syntax, run the example program and then solve the practice tasks to make the concept strong.