//  Stack.C
//
//  implements the Stack class described
// in the lecture notes for CS341 Spring 1998

#include <iostream.h>
#include "Stack.h"

// default constructor
//template <class Element_Type> 
//Stack<class Element_Type>::Stack( )
//{
//  Stack_Array = new Element_Type [Default_Size];
//  Top_Of_Stack = -1;
//  Full_Stack = Default_Size;
///
//  cout << "created a default stack" << endl;
//}

// construct Stack with N elements
template <class Element_Type>
Stack<Element_Type>::Stack(unsigned int N)
{
  Stack_Array = new Element_Type [N];
  Top_Of_Stack = -1;
  Full_Stack = N;

  cout << "created a stack with size " << N << endl;
}

// Pop()
//   "remove" the element at the
// the top of the stack by just
// decrementing the index
template <class Element_Type>
void Stack<Element_Type>::Pop()
{
  if (! isEmpty())
	--Top_Of_Stack;
  else
    cout << "Tried to Pop() empty stack" << endl;
}

// Push ()
//   insert a data element on the
// top of the stack
template <class Element_Type>
void Stack<Element_Type>::Push (const Element_Type& X)
{
    if (! isFull())
        Stack_Array[++Top_Of_Stack] = X;
    else
        cout << "Tried to Push() onto full stack" << endl;
}

// Pop_And_Top
// remove and return the top element of the stack
template <class Element_Type>
Element_Type Stack<Element_Type>::Pop_And_Top ()
{
    if (! isEmpty())
        return Stack_Array[Top_Of_Stack--];

    // else what if stack is empty??
        return Element_Type(0);
}

// Top()
// return const reference to the element
// on the top of the stack without removing it

template <class Element_Type>
const Element_Type& Stack<Element_Type>::Top() const
{
    if (! isEmpty())
        return Stack_Array[Top_Of_Stack];

    // else -- what if stack is empty??
        return Element_Type(0);
}