Discuss function overloading with example.

 Function overloading is a feature in C++ that allows us to have multiple functions with the same name, but with different parameters. The compiler decides which function to call based on the number, type, and order of the parameters passed.

Here's an example to demonstrate function overloading:

#include <iostream>
using namespace std;
// Function to calculate area of a square
int area(int side) {
    return side * side;
}
// Function to calculate area of a rectangle
int area(int length, int breadth) {
    return length * breadth;
}
// Function to calculate area of a circle
float area(float radius) {
    return 3.14 * radius * radius;
}
int main() {
    int s = 5, l = 10, b = 5;
    float r = 2.5;
    cout << "Area of square with side " << s << " is " << area(s) << endl;
    cout << "Area of rectangle with length " << l << " and breadth " << b << " is " << area(l, b) << endl;
    cout << "Area of circle with radius " << r << " is " << area(r) << endl;
    return 0;
}

In this example, we have defined three functions named area with the same name but different parameters. The first function calculates the area of a square, the second function calculates the area of a rectangle, and the third function calculates the area of a circle.

When we call the area function in the main function with different parameters, the compiler decides which function to call based on the type and number of parameters passed. For example, when we pass an integer parameter to the area function, the compiler calls the function that takes an integer parameter, and when we pass a float parameter, the compiler calls the function that takes a float parameter.

This is how function overloading works in C++.