Hmmm, so why am I getting 10 strange errors that all point to xutility? Below code is what I'm using. Here is a sample of one of the errors:

c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\xutility(98): error C2039: 'iterator_category' : is not a member of 'Point'

Code:

#include <iostream>
#include <cmath>
using namespace std;
const double PI = 2.0*asin(1.0);
class Point
{
protected:
double x, y;
public:
Point(double, double);
double area(){return 0;}
double distance(Point&, Point&);
};
Point::Point(double XX, double YY)
{
x = XX;
y = YY;
}
double Point::distance(Point& pt1, Point& pt2)
{
return sqrt(pow((pt2.x-pt1.x), 2)+pow((pt2.y-pt1.y),2));
}
class Circle : public Point
{
protected:
double radius;
public:
Circle(double rad, double x, double y) : radius(rad), Point(x, y) {}
double area(Circle&);
};
double Circle::area(Circle& myCircle)
{
return PI*pow(myCircle.radius, 2);
}
int main()
{
Point myPoint(1.3, 4.5);
Point myPoint1(3.2, 3.4);
cout << "The distance between the two points created is " << distance(myPoint, myPoint1) << endl;
Circle myCircle(10.0, 4.5, 6.5);
return 0;
}