Notes

#ifndef DYNAMICSTACK_H
#define DYNAMICSTACK_H
#include <iostream>
using namespace std;

// Stack template
template <class T>
class DynamicStack
{
private:
// Structure for the stach nodes
struct StackNode
{
T value; // Value in the node
StackNode *next; // Pointer to next node
};

StackNode *top; // Pointer to the stack top

public:
//Constructor
DynamicStack()
{ top = NULL; }

// Destructor
~DynamicStack();

// Stack operations
void push(T);
void pop(T &);
bool isEmpty();
};

//***************************************************
// Destructor *
//***************************************************
template <class T>
DynamicStack<T>::~DynamicStack()
{
StackNode *nodePtr, *nextNode;

// Position nodePtr at the top of the stack.
nodePtr = top;

// Traverse the list deleting each node.
while (nodePtr != NULL)
{
nextNode = nodePtr->next;
delete nodePtr;
nodePtr = nextNode;
}
}

//*************************************************************
// Member function push pushes the argument onto *
// the stack. *
//*************************************************************

template <class T>
void DynamicStack<T>::push(T item)
{
StackNode *newNode; // Pointer to a new node

// Allocate a new node and store num there.
newNode = new StackNode;
newNode->value = item;

// If there are no nodes in the list
// make newNode the first node.
if (isEmpty())
{
top = newNode;
newNode->next = NULL;
}
else // Otherwise, insert NewNode before top.
{
newNode->next = top;
top = newNode;
}
}

//*************************************************************
// Member function pop pops the value at the top *
// of the stack off, and copies it into the variable *
// passed as an argument. *
//*************************************************************

template <class T>
void DynamicStack<T>::pop(T &item)
{
StackNode *temp; // Temporary pointer

// First make sure the stack isn't empty.
if (isEmpty())
{
cout << "The stack is empty.n";
}
else // pop value off top of stack
{
item = top->value;
temp = top->next;
delete top;
top = temp;
}
}

//*************************************************************
// Member function isEmpty returns true if the stack *
// is empty, or false otherwise. *
//*************************************************************

template <class T>
bool DynamicStack<T>::isEmpty()
{
bool status;

if (!top)
status = true;
else
status = false;

return status;
}
#endif