Program of simple inheritance

#include<iostream.h>

#include<conio.h>

class circle

{

protected:

double radius;

public:

circle(double r);

double calclval();

};

void main()

{

circle::circle(1.0);

}

void circle::calclval()

{

double r;

r=radius*radius*3.15;

radius;

}

class cylinder:public circle

{protected:

double length;

public:

cylinder();

double calclval();

};

void cylinder::calclval()

{

double area=3.14*v*v*l;

}