Help with doubly linked list

[caladan21ph]

Hi! I'm having trouble with implementing the remove method of my doubly linked list. Here's my code:

#pragma once

#include <cassert>

template<typename T>
struct LinkedNode
{
	
	T data;
	LinkedNode* next;
	LinkedNode* prev;

};





template<typename T>
class LinkedList
{
public:
	LinkedList(void);
	~LinkedList(void);
	LinkedList(const LinkedList& rhs);
	LinkedList& operator=(LinkedList& rhs);

	bool isEmpty();
	LinkedNode<T>* getFirst();
	LinkedNode<T>* getLast();

	void insertFirst(T data);
	void insertLast(T data);
	bool insertAfter(T key,T data);
	void insertBefore(T key,T data);
	void removeFirst();
	void removeLast();
	bool remove(T removalCandidate);
	void destroy();


private:
	LinkedNode<T>* mLast;
	LinkedNode<T>* mFirst;

	


};

template<typename T>
LinkedList<T>::LinkedList(void)
{
	mFirst=0;
	mLast=0;
}

template<typename T>
LinkedList<T>::~LinkedList(void)
{
}

template<typename T>
LinkedNode<T>* LinkedList<T>::getFirst()
{
	return mFirst;
}

template<typename T>
LinkedNode<T>* LinkedList<T>::getLast()
{
	return mlast;
}


template<typename T>
bool LinkedList<T>::isEmpty()
{
	if(!mLast && !mFirst) return true;

	return false;
}


template<typename T>
void LinkedList<T>::insertFirst(T data)
{
	LinkedNode<T>* newNode=new LinkedNode<T>;
	newNode->data=data;

	if(isEmpty())
	{
		mLast=newNode;
	}

	else
	{
		mFirst->prev=newNode;
	}
	newNode->next=mFirst;
	mFirst=newNode;
}

template<typename T>
bool LinkedList<T>::insertAfter(T key,T data)
{
	if(isEmpty()) return false;


	LinkedNode<T>* current=mFirst;

	while(current->data!=key)
	{

		current=current->next;


		if(current==0) return false;


	}

	LinkedNode<T>* newNode=new LinkedNode<T> ;
	newNode->data=data;

	if(current==mLast)
	{
		newNode->next=0;
		mLast=newNode;

	}

	else
	{
		newNode->next=current->next;
		current->next->prev=newNode;
	}



	newNode->prev=current;
	current->next=newNode;


}


template<typename T>
bool LinkedList<T>::remove(T removalCandidate)
{

	if(isEmpty())return false;

	LinkedNode<T>* current=mFirst;

	while(current->data!=removalCandidate)
	{

		current=current->next;


		if(current==0) return false;
	}

	if(current==mLast)
	{
		mLast=current->prev;
		current->next=0;

	}

	if(current==mFirst)
	{
		mFirst=current->next;
		current->prev=-0;
	}
	
		
	else
	{
		current->prev->next=current->next;
		current->next->prev=current->prev;
	}
	
		
	
	delete current;
	current=0;
	

	return true;

}

I'm getting something like:

First-chance exception at 0x011516b5 in STL.exe: 0xC0000005: Access violation reading location 0x00000000.

I'm getting this stuff from a book but I have no way to check my work. Thanks!

[Lowest0ne]

It looks like you never set the next and prev pointers to NULL (not zero btw), so Line 159 goes beyond your list and then tries to use it as its own.

I would change the Node struct, and also the code when you make new

template<typename T>
struct LinkedNode
{
  data;
  LinkedNode* next;
  LinkedNode* prev;

  LinkedNode(T data, LinkedNode* next = NULL, LinkedNode* prev = NULL)
  {
    this.data = data;
    this.next = next;
    this.prev = prev;
  }

};