Write a complete C++ program that uses a function called carea() to calculate area of a circle. The function carea() receives radius of float type and returns area of double type. The function main() gets a radius value from the user, calls carea(), and displays the result. The function carea() is local to main.

#include<iostream.h>

#include<conio.h>

void main()
{
double carea(float r)
{
double ar = (double) ( 3.14 * r * r );
return ar;
}


float rad;


cout<<  " \n Enter Radius :";
cin >>rad;


double area = carea(rad);


cout<<"\n The area of the circle of radius " << rad << " unit is " << area << "sq. unit ";


getch();


}