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Need help with difficult copy constructor for derived class

Khillz3000 (68)
I have been looking at examples of copy constructors for derived classes but I really don't understand how I'm supposed write this one. I have three classes LinkList, CD, and Media. I have written copy constructors for Media and LinkList but not CD which is a derived class of Media and has a LinkList for its member variable. Please any help with this would be greatly appreciated.

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template <class T>
class LinkList
{
		private:
		
		struct ListNode
		 {
			 T value1;                
			 struct ListNode *next;  
		 }; 

		ListNode *head;   // List head pointer
	
		public:
		//***Constructor***
		LinkList();
		LinkList(const LinkList<T> &);
		//***Destructor***
		~LinkList();
		

		//***LinkList Operations***
		
		    //....operation functions
};		
//***Constructor***
template <class T>
LinkList<T>::LinkList()
{
	head = NULL;
}

//***Copy Constructor***
template <class T> 
LinkList<T>::LinkList( const LinkList &listObj )
{

	head = NULL;

	ListNode *nodePtr;

	nodePtr = listObj.head;

	while(nodePtr != NULL)
	{
		 appendNode(nodePtr->value1);
		
		 nodePtr = nodePtr->next;
	}

}


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class Media
{
	private:
		
		string title;
		string length;
		

	public:
		
		//***Constructors***
		Media();
		Media(string, string);
		Media(const Media &obj);
		//***destructor***
		~Media();
		
		//***Mutators***
		void setTitle(string);
		void setLength(string);

		//***Accessors***
		string getTitle();
		string getLength();

		//Overloaded Operators
		
		bool operator < (const Media &);
		bool operator > (const Media &);
		bool operator != (const Media &);
		bool operator == (const Media &right);
};

/*****Implimentation*********/
//***Constructors***
Media::Media()
{
	title = "  ";
	length = " ";
}

//***Constructors***
Media::Media(string t, string l)
{
	title = t;
	length = l;
}

//***Copy Constructor***
Media::Media(const Media &obj)
{
	title = obj.title;
	length = obj.length;
}


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//LinkList structure for CD class

struct CdContence
{
	string song;
	string length;
};



class CD : public Media
{
	public:
		
		LinkList<CdContence> Cd;
		
	public:
		
		//***Constructors***
		CD(string, string);
	    CD();
		
		//***destructor***
		~CD();
		
		//***Mutators***
		void setCD(string, string, string, string);
		
		//***Accessors***
		LinkList<CdContence> getCD();
	

		//Overloaded Operators
		
		bool operator < (CD &);
		bool operator > (CD &);
		bool operator != (CD &);
		bool operator == (CD &);
};

/*****Implimentation*********/
//***Constructors***
CD::CD(string T, string L)
{
	setTitle(T);
	setLength(L);
	LinkList<CdContence>Cd;
	cout<<"CD CONSTRUCTOR2"<<endl;
}

CD::CD() : Media()
{
	LinkList<CdContence>Cd;

	cout<<"CD CONSTRUCTOR"<<endl;
}

CD::CD(const CD &obj) :Media(obj)
{
	//not sure what to put here since the member variable is 
	// a linklist
	
}
Khillz3000 (68)
Is this right? I'm gettin' desperate here!

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CD::CD(const CD &obj) :Media(obj),Cd(obj.Cd)	
{}


I put it in and the program froze after I entered a data for a second CD. Please anyone...
cire (8284)
Neither Media, nor CD need explicitly defined copy constructors. The defaulted versions will be adequate. As I mentioned other-thread, the copy assignment operator for LinkList should be defined.

In the CD constructors you are defining a local-to-the-constructor LinkList which immediately goes out of scope. This doesn't harm anything, but it certainly isn't necessary.

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//***Constructors***
CD::CD(string T, string L) : Media(T, L)
{
	cout<<"CD CONSTRUCTOR2"<<endl;
}

is the most efficient way to define this constructor.
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