Sum of Two Objects

#include<iostream>
using namespace std;
class Point;
class Distance;
class Point
{
int PointValue;
public:
	void ReadValue(int v)
	{
		PointValue = v;
	}
friend int sumValues(const Point&, const Distance&);
};

class Distance
{
int DistanceValue;

public:
	void ReadValue(int v)
	{
		DistanceValue = v;
	}
friend int sumValues(const Point&, const Distance&);
};

int sumValues(const Point& p, const Distance& d)
{
    return (p.PointValue + d.DistanceValue);
}

int main()
{
	Point P1;
	Distance D1;

	int PointV,DistanceV;
	cin>>PointV;
	P1.ReadValue(PointV);
	cin>>DistanceV;
	D1.ReadValue(DistanceV);
	cout<<"Sum="<<sumValues(P1,D1);
}