C++ Function Overriding

🎭 C++ Function Overriding – One Thing, New Way in Derived Class

In C++, function overriding means giving a new meaning to a function that’s already defined in a base class — but inside the derived class. It’s like your own way of doing something your parents also did! 😄

🔁 What is Overriding?

Overriding happens when a derived class defines a function that has the same name, return type, and parameters as a function in its base class.

To enable overriding, the base class should use the virtual keyword in the function.

📦 Syntax of Function Overriding

class Base {
public:
    virtual void show() {
        // base class version
    }
};

class Derived : public Base {
public:
    void show() override {
        // derived class version
    }
};

🔧 Example: Simple Overriding

#include <iostream>
using namespace std;

class Animal {
public:
    virtual void sound() {
        cout << "Animal makes sound" << endl;
    }
};

class Dog : public Animal {
public:
    void sound() override {
        cout << "Dog barks!" << endl;
    }
};

int main() {
    Animal* a;
    Dog d;
    a = &d;

    a->sound();  // Dog's version will run

    return 0;
}
  

🧠 Why Use Overriding?

• To customize behavior of inherited methods
• Useful in polymorphism – base pointers calling derived methods
• Gives flexibility and extensibility to your code

🚨 Rules of Overriding

• Function must have the same signature
• Base class function should be virtual
• Use override keyword (C++11+) for clarity

❓ Override vs Overload

• Overriding: Same name, same parameters, different class
• Overloading: Same name, different parameters, same class

🧾 Summary

• Overriding means giving new behavior to a base class method
• Needs virtual in base and override in derived (recommended)
• Used in runtime polymorphism
• Remember: one thing, more than one version = override! 🎭