stack.h

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//start id="classdef"
#include <qstd.h>

/** 
    A node in a linked list 
*/
template<class T> class Node {
 public:
    Node(T invalue): m_Value(invalue), m_Next(0) {}
    ~Node() ;
    T getValue() const {return m_Value;}
    void setValue(T value) {m_Value = value;}
    Node<T>* getNext() const {return m_Next;}
    void setNext(Node<T>* next) {m_Next = next;}
 private:
    T m_Value;
    Node<T>* m_Next;
};

template<class T> Node<T>::~Node() {
    using namespace qstd;
    cout << m_Value << " deleted " << endl;
    if(m_Next) {
        delete m_Next; 
    }
}

/**
   A template-generic stack implemented as a single-linked list.
*/

template<class T> class Stack {
 public:
    Stack(): m_Head(0), m_Count(0) {}
    ~Stack<T>() {delete m_Head;} ;
    void push(const T& t);
    T pop();
    T top() const;
    int count() const;
 private:
    Node<T> *m_Head;
    int m_Count;
};

//end



/** Notice the function definitions are all in the header file.
    This is necessary for the compiler to generate code from
    a template declaration. */

//start id="fundef"

template <class T> void Stack<T>::push(const T& value) {
    Node<T> *newNode = new Node<T>(value);
    newNode->setNext(m_Head);
    m_Head = newNode;
    ++m_Count;
}

template <class T>  T Stack<T>::pop() {
    Node<T> *popped = m_Head;
    if (m_Head != 0) {
        m_Head = m_Head->getNext();
        T retval = popped->getValue();
        popped->setNext(0);
        delete popped;
        --m_Count;
        return retval;        
    }
    return 0;
}
//end

template <class T> inline T Stack<T>::top() const {
    return m_Head->getValue();   
}

template <class T> inline int Stack<T>::count() const {
    return m_Count;
}