Answer Posted / pradeep

This example fully describe the need of Virtual Destructor
in base class:-
----------------------------------------------------------
#include <iostream.h>
#include <stdio.h>
class Base
{
public:
Base(){ cout<<"Constructor: Base"<<endl;}
~Base(){ cout<<"Destructor : Base"<<endl;}
};
class Derived: public Base
{
//Doing a lot of jobs by extending the functionality
public:
Derived(){ cout<<"Constructor: Derived"<<endl;}
~Derived(){ cout<<"Destructor : Derived"<<endl;}
};
void main()
{
Base *Var = new Derived();
delete Var;
getch();
}

-----------------------------------------------------------
When it will be executed..it will show only that Base Class
destructor executed not the Derived.
But if we make Base class destructor "virtual"
(i.e. virtual ~Base(){ cout<<"Destructor : Base"<<endl;} )
then we can verify that Destructor execute into this order:--
1. Derived class destructor
2. Base class destructor

---If there is any mistake kindly let me know.
Thanks...!!!

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