оператор извлечения >> и вставки <<

Как Перегрузить оператор извлечения >> и вставки << для объектов данного класса.

  #include <iostream>
#include <math.h>
using namespace std;
class Vector
{
public:
    double X;
    double Y;
    double Z;
    Vector()
    {
        this->X = 0;
        this->Y = 0;
        this->Z = 0;
    }
    Vector(double x, double y, double z)
    {
        this->X = x;
        this->Y = y;
        this->Z = z;
    }
    double GetLength()
    {
        return sqrt(X * X + Y * Y + Z * Z);
    }
    void Print()
    {
        cout << endl;
        cout << "X=" << X;
        cout << endl;
        cout << "Y=" << Y;
        cout << endl;
        cout << "Z=" << Z;
        cout << endl;
    }
    Vector operator +(Vector r)
    {
        return Vector(this->X + r.X, this->Y + r.Y, this->Z + r.Z);
    }
    Vector operator -(Vector r)
    {
        return Vector(this->X - r.X, this->Y - r.Y, this->Z - r.Z);
    }
    double operator *(Vector r)
    {
        return (this->X * r.X + this->Y * r.Y + this->Z * r.Z);
    }
};
int main()
{
    int n1;
    cout << "Vvedite kolishstvo elementov massiva: ";
    cin >> n1;
    Vector* vc=new Vector[n1]();//создаём динамический массив 
    for (size_t i = 0; i < n1; i++)//заполняем массив
    {
        double x1, y1, z1;
        cout << "Vvedite  X[" << i << "]" << " Y[" << i << "]" << " Z[" << i << "]" << endl;
        cin >> x1 >> y1 >> z1;
        vc[i].X = x1;
        vc[i].Y = y1;
        vc[i].Z = z1;
    }
    Vector sum;
    Vector raz=vc[0];
    for (size_t i = 0; i < n1; i++)
    {
        sum =sum+ vc[i];
        if (i == 0)
        {
            continue;
        }
        raz = raz - vc[i];
    }
    cout << "Summa" << endl;
    cout << sum.X << " " << sum.Y << " " << sum.Z << endl;
    cout << "Raznost" << endl;
    cout << raz.X << " " << raz.Y << " " << raz.Z << endl;
    delete[] vc;
    system("pause");
}