Write a C++ program that computes the area of a circle

 

Write a program that computes the area of a circle. The formula to find the area of a circle is:   

• area = PI*R*R. The value of PI is 3.1417. 
• Store the value of PI in a constant using ‘define’ directive 

#include<iostream.h>
#include<conio.h>
#define PI 3.1417
void main(void)
{
    float R, area;
    R = 10;
    area = PI*R*R;
    clrscr();
    cout << "Area of a circle is = " << area;
    getch();
}