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Unhandled exception error

joemaz1207 (1)
I am having trouble running my code. It all compiles, but when i run it u get this error
"Unhandled exception at 0x001f18ac in Project 2.exe: 0xC0000005: Access violation reading location 0x00000004."

If anyone knows how to fix this I would greatly appreciate it
This must be done using a linked list stack

This is my header file
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template <class DataType>
struct Node{
	DataType info;
	Node<DataType>*next;
};

template <class DataType>
class Stack
{
public:
	Stack();
	void push(DataType elementToPush);
	bool pop(DataType & poppedElement);
	Stack(const Stack<DataType> &element); // Copy constructor
	~Stack(); // Destructor
	Stack<DataType> & operator=(const Stack<DataType> &element); //Overload assignment operator
	bool isEmpty()const;
	void makeEmpty();
private:
	Node<DataType>*top;
	inline void deepCopy(const Stack<DataType> & original);
};

template<class DataType>
Stack<DataType>::Stack()
{
	top=NULL;
}

template<class DataType> // Remove the node at the front of the list and return the element
bool Stack<DataType>::pop(DataType & element)
{
	if (isEmpty()==true)
		return false;
	else
	{
		Node<DataType>*ptr=top->next;
		top->next=ptr->next;
		element=ptr->info;
		delete ptr;
		return true;
	}
}

template<class DataType> // Make a new node for the element and push it to the front of the list
void Stack<DataType>::push(DataType element)
{
	Node<DataType>*ptr=new Node<DataType>;
	ptr->info=element;
	ptr->next=top->next;
	top->next=ptr;
}

template<class DataType> // Check to see if the list is empty
bool Stack<DataType>::isEmpty()const
{
	return top==NULL;
}

template<class DataType> // Empty the list out
void Stack<DataType>::makeEmpty()
{
	while (top->next != NULL)
	{
		Node<DataType>*ptr=top->next;
		top->next=ptr->next;
		delete ptr;
	}
}

template<class DataType> // Deep copy
inline void Stack<DataType>::deepCopy(const Stack<DataType> & original)
{
	Node<DataType>*copyptr=new Node<DataType>;
	Node<DataType>*newtop=copyptr;
	Node<DataType>*originalptr=top->next;
	while(originalptr != NULL)
	{
		originalptr=originalptr->next;
		copyptr->next=new Node<DataType>;
		copyptr=copyptr->next;
		copyptr->info=originalptr->info;
		
	}
}

template<class DataType> // Copy Constructor
Stack<DataType>::Stack(const Stack<DataType> &element)
{
	deepCopy(element);
}

template<class DataType> // Destructor
Stack<DataType>::~Stack()
{
	makeEmpty();
}

template<class DataType> // Overload assignment operator
Stack<DataType> & Stack<DataType>::operator=(const Stack<DataType> &element)
{
	if(this == &element)
		return *this;
	makeEmpty();
	deepCopy(element);
	return *this;
}


And this is the main file provided by my professor
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#include <iostream >
#include "stack.h"
using namespace std ;
int main ()
{
	Stack < int > s1 , s2 ;
	int element ;

	s1 . push (1); s1 . push (2); s1 . push (3);
	s1 . pop ( element );
	cout << " s1 popped element : " << element << endl ;

	s2 = s1 ;
	s2 . push (4);
	s2 . pop ( element );
	cout << " s2 popped element : " << element << endl ;

	s1 . pop ( element );
	cout << " s1 popped element : " << element << endl ;

	s2 . makeEmpty ();
	s2 . isEmpty () ? cout << " s2 is empty \n": cout << " s2 is not empty \n ";
	
	system ("pause");
	return 0;
}

ne555 (10692)
http://www.cplusplus.com/forum/general/112111/
In instantiation of ‘void Stack<DataType>::deepCopy(const Stack<DataType>&) [with DataType = int]’:
73:63: warning: unused parameter ‘original’ [-Wunused-parameter]
your copy does not use the value to copy from
that can't be right

Also 
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#include <iostream >
//                ^that space shouldn't be there
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