/*--------------------------------------------------
created by st10 at Mon Apr  2 16:43:01 PDT 2007
--------------------------------------------------*/
#include <iostream>
#include <cmath>
using namespace std;


/*--------------------------------------------------
 Contract: circ_area : double -> double
 Purpose: return the area of a circle whose radius is
          <radius>

 Examples: circ_area(10) == 314.159
--------------------------------------------------*/
double circ_area(double radius)
{
    return 3.14159 * (radius * radius);
}