In which order are constructors and destructors called?

#ifndef __ORDER_H__

#define __ORDER_H__

class parent

{

public:

parent();

~parent();

};

class child : public parent

{

public:

child();

~child();

};

class grandchild : public child

{

public:

grandchild();

~grandchild();

};

#endif /* __ORDER_H__ */

#include "order.h"

#include <iostream.h>

parent::parent()

{

cout << "in parent's constructor" << endl;

}

parent::~parent()

{

cout << "in parent's destructor" << endl;

}

child::child()

{

cout << " in child's constructor" << endl;

}

child::~child()

{

cout << " in child's destructor" << endl;

}

grandchild::grandchild()

{

cout << " in grandchild's constructor" << endl;

}

grandchild::~grandchild()

{

cout << " in grandchild's destructor" << endl;

}

#include "order.h"

int main()

{

grandchild * gc = new grandchild();

delete gc;

}

$ main

in parent's constructor

in child's constructor

in grandchild's constructor

in grandchild's destructor

in child's destructor

in parent's destructor

Answer: constructors top-down, destructors bottom-up.

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