Hierarchical Inheritance.

Write a C++ program to find out the area of the rectangle and triangle using hierarchical inheritance.

Program Algorithm:

Step 1: Include the header files

Step 2: Declare the base class polygon.

Step 3: Declare and define the function input () to get the width and height.

Step 4: Declare the two derived classes rectangle and triangle.

Step 5: Calculate the area using width and height.

Step 6: Create objects for the derived classes.

Step 7: Declare the derived class object, call the functions input () and calculate the area.

Program Code in C++:

#include<iostream.h>

#include<conio.h>

class polygon

{

protected:

int width, height;

public:

void input(int x, int y)

{

width = x;

height = y;

}

};

class rectangle : public polygon

{

public:

int areaR ()

{

return (width * height);

}

};

class triangle : public polygon

{

public:

int areaT ()

{

return (width * height / 2);

}

};

void main ()

{ 

clrscr();

rectangle rect;

triangle tri;

rect.input(6,8);

tri.input(6,10);

cout <<"Area of Rectangle: "<<rect.areaR()<< endl;

cout <<"Area of Triangle: "<<tri.areaT()<< endl;

getch();

}

Program Output:

Area of Rectangle: 48

Area of triangle: 30