#include<iostream>

#include<cmath>

using namespace std;

 

class MyPoint

{

private:

    double x, y;

public:

    // The no-arg constructor that contruccts a point with coordinates(0,0)

    MyPoint();

    MyPoint(double x, double y);

    double getX() const;

    double getY() const;

 

    //display the distance between two points in two-dimensional space.

    double distance(const MyPoint &point);

};

MyPoint::MyPoint() {

 x=0.0;

 y=0.0;

}

 

MyPoint::MyPoint(double x,double y){

 this->x = x;

 this->y = y;

} 

double MyPoint::getX() const{

    return x; 

}

 

double MyPoint::getY() const{

    return y; 

}

 

double MyPoint::distance(const MyPoint &point){

 double a=this->x - point.x;

 double b=this->y - point.y;

 return sqrt( pow(a,2) + pow(b,2) );

}

 

 

 

class ThreeDPoint : public MyPoint

{

private:

    double z;

public:

    // The no-arg constructor that contruccts a point with coordinates(0,0,0)

    ThreeDPoint();

 

    ThreeDPoint(double x, double y, double z);

    double getZ() const;

 

    //display the distance between two points in Three-dimensional space.

    double distance(const ThreeDPoint &point);

};

ThreeDPoint::ThreeDPoint():MyPoint(){

 z=0.0;

}

ThreeDPoint::ThreeDPoint(double xx,double yy,double z):MyPoint(xx,yy){

 this->z = z;

}

double ThreeDPoint::getZ() const{

    return z;

}

double ThreeDPoint::distance(const ThreeDPoint &point){

 

 double a = this->getX()-point.getX();

 double b = this->getY()-point.getY();

 double c = this->z-point.z;

 return sqrt(pow(a,2) + pow(b,2) + pow(c,2));

}

 

 

 

 

 

int main(){

 

 

 

 

 return 0;

}