Write a class with constructors and destructors functions.

Question

A point in a two-dimensional plane having coordinate as (x,y), can be represented by a class whose private data members are x and y. Write the constructor and destructor functions of the class. The constructor should initialise (x,y) by passing parameters values. Now, a rectangle can be represented by the top-left and bottom-right vertices. Define a class say ‘Rectangle’ whose private data members are top-left and bottom-right vertices. Write the parameterised constructor function of the class ‘Rectangle’. Also, write the destructor function. Finally, write a program to show the order in which different constructors and destructors are called.

Answer 1

using namespace std;

#include <iostream>

class Point

{

private:

double x;

double y;

public:

Point( double X, double Y)

{

x=X; y=Y;

cout << " Point constructor : x = "<< x << " : y = " << y << endl;

}

//copy constructor

Point (Point& p)

{

double X = p.GetX();

double Y = p.GetY();

this->x = X;

this->y = Y;

}

~Point()

{

cout << " Point destructor : x = "<< x << " : y = " << y << endl;

}

double GetX() { return(x); }

double GetY() { return(y); }

void Show()

{

cout << "("<<x<<","<<y<<")"<<endl;

}

};

class Rectangle

{

private:

Point * topLeft;

Point * bottomRight;

public:

Rectangle( Point top_left, Point bottom_right)

{

topLeft = new Point(top_left);

bottomRight = new Point(bottom_right);

cout << "Rectangle constructor : top left at:";

this->topLeft->Show();

cout << "Rectangle constructor : bottom right at: ";

this->bottomRight->Show();

}

//copy constructor

Rectangle (Rectangle& r)

{

topLeft = new Point (*r.topLeft);

bottomRight = new Point(*r.bottomRight);

}

~Rectangle()

{

cout << "Rectangle destructor : top left at:";

this->topLeft->Show();

cout << "Rectangle destructor : bottom right at: ";

this->bottomRight->Show();

if (topLeft!=NULL) { delete(topLeft); }

if (bottomRight != NULL) { delete(bottomRight); }

}

};

int main()

{

Point topLeft(1,3);

Point bottomRight(7,5);

Rectangle r(topLeft,bottomRight);

return 0;

}