C++ Function Overloading

Overloading means use of same thing for different purposes. Using function overloading we can perform different tasks with the same function name depending on the argument list. Function overloading is a concept of polymorphism.

Rules while creating function overloading:

1. Name of the all functions is same
2. Argument list or data type is different
3. Return type does not matters

Example 1: Find sum of 2 numbers and 3 numbers using function overloading.

#include<iostream.h>

using namespace std;

//function declaration
int sum (int , int);
int sum (int , int, int );

int main()
{
    int a, b, c, sum1, sum2;
    cout<<"Enter 2 numbers: ";
    cin>>a;
    cin>>b;
    sum1 = sum(a, b);  // function call
    cout<<"Sum of 2 numbers is: "<<sum1;

    cout<<"Enter 3 numbers: ";
    cin>>a;
    cin>>b;
    cin>>c
    sum2 = sum(a, b, c); //! function call
    cout<<"Sum of 3 numbers is: "<<sum2;
    return 0;
}

// function definition
int sum (int a, int b)
{
    int c;
    c = a+b;
    return c;
}

int sum (int a, int b , int c)
{
    int d;
    d = a+b+c;
    return d;
}

2. Find area of circle and rectangle using function overloading.

#include<iostream.h>
#include<conio.h>

float area (float r);  // function declaration for area of circle
int area (int l, int b); // function declaration for area of rectangle

void main()
{
    clrscr();
    float r, a2;
    int l, b, a1;
    
    cout<<"Enter radius of circle: ";
    cin>>r;

    cout<<"Enter Length of rectangle: ";
    cin>>l;
    cout<<"Enter Breadth of rectangle: ";
    cin>>b;

    a1 = area(l,b); //function calling (rectangle)
    a2 = area(r); //function calling (circle)

    cout<<"Area of Circle = "<< a2 << endl;
    cout<<"Area of Rectangle = "<< a1;
    getch();
}

float area (float r)
{
    float a;
    a = 3.14 * r * r;
    return a;
}

int area (int l, int b)
{
    int a;
    a = l * b;
    return a;
}
Output:
	Enter radius of circle: 5
	Enter Length of rectangle: 10
	Enter Breadth of rectangle: 20
	Area of Circle = 78.5
	Area of Rectangle = 200

3. WAP to calculate area of circle, rectangle, and triangle using function overloading.

#include <iostream>
using namespace std;

int area (int l, int b);
float area (float r);

int area (int s)
{
    int a;
    a = s*s;
    return a;
}

int main()
{
    int n, l, b, a, s;
    float r, a2;
    cout << "Enter number to find area\n";
    cout << "1 - Rectangle"<<endl;
    cout << "2 - Circle"<<endl;
    cout << "3 - Square"<<endl;
    cin>>n;
    switch(n)
    {
        case 1:
            cout<<"Enter length, breadth";
            cin>>l>>b;
            a=area(l,b);
            cout<<"Area of Rectangle = " << a;
        break;
        case 2:
            cout<<"Enter Radius";
            cin>>r;
            a2=area(r);
            cout<<"Area of Circle = " << a2;
        break;
        case 3:
            cout<<"Enter side";
            cin>>s;
            a=area(s);
            cout<<"Area of Square = " << a;
        break;
    }
    return 0;
}
int area (int l, int b)
{
    int a;
    a = l * b;
    return a;
}
float area (float r)
{
    float a2;
    a2 = 3.14 * r*r;
    return a2;
}