#include<stdio.h>
double aoc(double r);
int main()
{
   double r,a;

    printf("Enter the value of radius of circle :");
    scanf("%lf",&r);
    a=aoc(r);
    printf("The area of the circle is :%lf\n",a);

return 0;
}
double aoc(double r)
{

     double  area;
    area=3.14*r*r;

    return area;



}