private double d(ToaDo a, ToaDo b)
{
Coordinates toaDo1 = new Coordinates(a);
Coordinates toaDo2 = new Coordinates(b);
double doDai = CoordinatesDistanceExtensions.DistanceTo(toaDo1, toaDo2) * 1000;// đơn vị là mét.
return(doDai);
}
public Coordinates(ToaDo toaDo)
{
Latitude = toaDo.getX();
Longitude = toaDo.getY();
}