program on macros example 3

PROGRAM FOR MACROS EXAMPLE 3

#define PI 3.142857

void main()

{

    float r,a;

    printf("Enter radius of a circle:");

    scanf("%f",&r);

    a=PI*r*r;

    printf("Area of circle:%f",a);

}

OUTPUT:

Enter radius of circle: 3

Area of circle: 285713