Question

1. Write a virtual member function named length , which specifies that the function is constant (that is does not modify the member data) and returns the square root of x squared plus y squared.

2.write the operator << function to have a member of the ostream class as its left hand operand and a member of the Two Dimensions class as its right hand operand. This function shall take the left hand operand by reference, This function shall return a reference to the left hand operand by reference, and the right hand operand by constant reference. This function shall return a reference to the left hand operand by reference. It shall print the values of X,Y and length to the ostream object that is the left hand operand.

3.Write the operator<, function for the Three Dimensions class. It shall print the values of x y z and length to the ostream object that is the left hand operand.

4. Why cant the operator << function that works with the TwoDimensions class be written as a member function.

5. write a length function that returns the square root x squared plus y square plus z square

Answer 1

//Written class for TwoDimentions,

This is the base class from which ThreeDimentions class inherits. In main , creating pointer to object of class TwoDimentions , hence providing virtual function for setting value of third point z and getting third point z.

#include<iostream>

#include<cmath>

using namespace std;

class TwoDimensions

{

int x,y;

public:

TwoDimensions()

{

x=0;

y=0;

}

void setX(int v)

{

x=v;

}

void setY(int v)

{

y=v;

}

virtual void setZ(int v)

{

}

virtual void getZ() const{

}

int getX() const

{

return x;

}

int getY() const

{

return y;

}

friend ostream& operator<<(ostream &out,TwoDimensions &obj)

{

out<<"x= "<<obj.x<<", y = "<<obj.y<<endl;

return out;

}

virtual double length() const

{

return sqrt(getX()*getX()+ getY()*getY());

}

};

=================

//Written class for ThreeDimentions

#include"TwoDimensions.h"

class ThreeDimentions: public TwoDimensions

{

int z;

public:

ThreeDimentions():TwoDimensions()

{

z=0;

}

void setZ(int v)

{

z=v;

}

friend ostream& operator<<(ostream &out,ThreeDimentions &obj)

{

out<<"x= "<<obj.getX()<<", y= "<<obj.getY()<<", z= "<<obj.z<<endl;

return out;

}

double length() const

{

return sqrt(getX()*getX()+getY()*getY()+z*z);

}

};

===============================

//Written Main.cpp two show the two objects TwoDimentions and ThreeDimentions

#include <iostream>

#include"ThreeDimensions.h"

using namespace std;

int main() {

//std::cout << "Hello World!\n";

//declare 2-dimentinal pointer

TwoDimensions *obj1,*obj2;

//set x and y of obj1

obj1=new TwoDimensions;

obj1->setX(10);

obj1->setY(20);

//set x,y and z of 3-d object obj2

obj2=new ThreeDimentions;

obj2->setX(10);

obj2->setY(20);

obj2->setZ(-5);

//print obj1 and obj2

cout<<"2-d object is : "<<endl<<*obj1<<endl;

cout<<"3-d object is : "<<endl<<*obj2<<endl;

cout<<"Length of 2-d object: "<<obj1->length()<<endl;

cout<<"Length of 3-d object: "<<obj2->length()<<endl;

}

=============================

//Output

2-d object is :
x= 10, y = 20

3-d object is :
x= 10, y= 20, z= -5

Length of 2-d object: 22.3607
Length of 3-d object: 22.9129