To calculate the area of  circle, rectangle and  triangle using function overloading.

• STEP 1:  Start the program.
• STEP 2:  Declare the class name as fn with data members and member functions.
• STEP 3:  Read the choice from the user.
• STEP 4:  Choice=1 then go to the step 5.
• STEP 5:  The function area() to find area of circle with one integer argument.
• STEP 6:  Choice=2 then go to the step 7.
• STEP 7:  The function area() to find area of rectangle with two integer argument.
• STEP 8:  Choice=3 then go to the step 9.
• STEP 9:  The function area() to find area of triangle with three arguments, two as Integer and one as float.
• STEP 10: Choice=4 then stop the program.

``````#include<iostream.h>
#include<stdlib.h>
#include<conio.h>
#define pi 3.14

class fn {
public:
void area(int); //circle
void area(int, int); //rectangle
void area(float, int, int); //triangle
};

void fn::area(int a) {

cout << "Area of Circle:" << pi * a*a;
}

void fn::area(int a, int b) {
cout << "Area of rectangle:" << a*b;
}

void fn::area(float t, int a, int b) {
cout << "Area of triangle:" << t * a*b;
}

void main() {
int ch;
int a, b, r;
clrscr();
fn obj;
cout << "\n1.Area of Circle\n2.Area of Rectangle\n3.Area of Triangle\n4.Exit\n:?;
cout << ?Enter your Choice : ";
cin>>ch;

switch (ch) {
case 1:
cout << "Enter Radious of the Circle:";
cin>>r;
obj.area(r);
break;
case 2:
cout << "Enter Sides of the Rectangle:";
cin >> a>>b;
obj.area(a, b);
break;
case 3:
cout << "Enter Sides of the Triangle:";
cin >> a>>b;
obj.area(0.5, a, b);
break;
case 4:
exit(0);
}
getch();
}``````

## Sample Output

``````Function Overloading
1. Area of Circle
2. Area of Rectangle
3. Area of Triangle
4. Exit