text: #include "MovablePoints.h"   // Include header of the base class
  
  //note that do not set default argument here, otherwise it could cause redefinition issue
  MovablePoint::MovablePoint(int x, int y,int xSpeed,int ySpeed)
      :Points(x,y),xSpeed(xSpeed),ySpeed(ySpeed){}//base class constructor
  
  int MovablePoint::getXSpeed() const{
      return xSpeed;
  }
  
  int MovablePoint::getYSpeed() const{
      return ySpeed;
  }
  
  void MovablePoint::setXSpeed(int xSpeed){
      this->xSpeed = xSpeed;
  }
  
  void MovablePoint::setYSpeed(int ySpeed){
      this->ySpeed = ySpeed;
  }
  
  void MovablePoint::print() const{
      std::cout<<"Movable";
      Points::print();
      std::cout<<" Speed="<<xSpeed<<" "<<ySpeed<<std::endl;
  }
  
  void MovablePoint::move(){
      Points::setX(Points::getX()+xSpeed);//base class member function
      Points::setY(Points::getY()+ySpeed);
  }