myStack.h

#ifndef H_StackType 
#define H_StackType

#include <iostream> 
#include <cassert>

#include "stackADT.h"

using namespace std;

template <class Type>
class stackType : public stackADT<Type>
{
public:
    const stackType<Type>& operator=(const stackType<Type>&);
    //Overload the assignment operator.

    void initializeStack();
    //Function to initialize the stack to an empty state.
    //Postcondition: stackTop = 0

    bool isEmptyStack() const;
    //Function to determine whether the stack is empty.
    //Postcondition: Returns true if the stack is empty,
    //               otherwise returns false.

    bool isFullStack() const;
    //Function to determine whether the stack is full.
    //Postcondition: Returns true if the stack is full,
    //               otherwise returns false.

    void push(const Type& newItem);
    //Function to add newItem to the stack.
    //Precondition: The stack exists and is not full.
    //Postcondition: The stack is changed and newItem 
    //               is added to the top of the stack.

    Type top() const;
    //Function to return the top element of the stack.
    //Precondition: The stack exists and is not empty.
    //Postcondition: If the stack is empty, the program 
    //               terminates; otherwise, the top element
    //               of the stack is returned.

    void pop();
    //Function to remove the top element of the stack.
    //Precondition: The stack exists and is not empty.
    //Postcondition: The stack is changed and the top 
    //               element is removed from the stack.

    int size() const;
    //Function to return the number of elements in the stack.

    stackType(int stackSize = 100);
    //constructor
    //Create an array of the size stackSize to hold 
    //the stack elements. The default stack size is 100.
    //Postcondition: The variable list contains the base
    //               address of the array, stackTop = 0, and  
    //               maxStackSize = stackSize.

    stackType(const stackType<Type>& otherStack);
    //copy constructor

    ~stackType();
    //destructor
    //Remove all the elements from the stack.
    //Postcondition: The array (list) holding the stack 
    //               elements is deleted.

private:
    int maxStackSize; //variable to store the maximum stack size
    int stackTop;     //variable to point to the top of the stack
    Type* list;       //pointer to the array that holds the
                      //stack elements
    int stackSize;    //variable to store the current size of the stack

    void copyStack(const stackType<Type>& otherStack);
    //Function to make a copy of otherStack.
    //Postcondition: A copy of otherStack is created and
    //               assigned to this stack.
};


template <class Type>
void stackType<Type>::initializeStack()
{
    stackTop = 0;
    stackSize = 0;
}

template <class Type>
bool stackType<Type>::isEmptyStack() const
{
    return (stackTop == 0);
}

template <class Type>
bool stackType<Type>::isFullStack() const
{
    return (stackTop == maxStackSize);
}

template <class Type>
void stackType<Type>::push(const Type& newItem)
{
    if (!isFullStack())
    {
        list[stackTop] = newItem;   //add newItem to the 
                                    //top of the stack
        stackTop++; //increment stackTop
        stackSize++; //increment stackSize
    }
    else
        cout << "Cannot add to a full stack." << endl;
}

template <class Type>
Type stackType<Type>::top() const
{
    assert(stackTop != 0);      //if stack is empty, 
                                //terminate the program
    return list[stackTop - 1];  //return the element of the
                                //stack indicated by 
                                //stackTop - 1
}

template <class Type>
void stackType<Type>::pop()
{
    if (!isEmptyStack()) {
        stackTop--;      //decrement stackTop
        stackSize--;     //decrement stackSize
    }
    else
        cout << "Cannot remove from an empty stack." << endl;
}

template <class Type>
int stackType<Type>::size() const
{
    return stackSize;
}

template <class Type>
stackType<Type>::stackType(int stackSize)
{
    if (stackSize <= 0)
    {
        cout << "Size of the array to hold the stack must "
            << "be positive." << endl;
        cout << "Creating an array of size 100." << endl;

        maxStackSize = 100;
    }
    else
        maxStackSize = stackSize;   //set the stack size to 
                                    //the value specified by
                                    //the parameter stackSize

    stackTop = 0;                   //set stackTop to 0
    list = new Type[maxStackSize];  //create the array to
                                    //hold the stack elements
    stackSize = 0;                  //initialize stackSize
}

template <class Type>
stackType<Type>::~stackType() //destructor
{
    delete[] list; //deallocate the memory occupied 
                    //by the array
}

template <class Type>
void stackType<Type>::copyStack
(const stackType<Type>& otherStack)
{
    delete[] list;
    maxStackSize = otherStack.maxStackSize;
    stackTop = otherStack.stackTop;
    stackSize = otherStack.stackSize;

    list = new Type[maxStackSize];

    //copy otherStack into this stack
    for (int j = 0; j < stackTop; j++)
        list[j] = otherStack.list[j];
}

template <class Type>
stackType<Type>::stackType(const stackType<Type>& otherStack)
{
    list = nullptr;

    copyStack(otherStack);
}

template <class Type>
const stackType<Type>& stackType<Type>::operator=
(const stackType<Type>& otherStack)
{
    if (this != &otherStack) //avoid self-copy
        copyStack(otherStack);

    return *this;
}

#endif