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顺序栈

//Stack.h
template<typename T,int Size=10>
class Stack
{
public:
    Stack();
    ~Stack();
    void push(const T &);
    void pop();
    T & top();
    bool empty();
    bool full();
private:
    T _arr[Size];
    int _top;
};

//Stack.cc
template<typename T,int Size>
Stack<T,Size>::Stack()
:_top(-1)
,_arr(new T[Size])
{}

template<typename T,int Size>
Stack<T,Size>::~Stack()
{
    delete [] _arr;
}

template<typename T,int Size>
void Stack<T,Size>::push(const T & elem)
{
    if(full())
    {
        cout << "full stack" << endl;
        return;
    }
    _arr[++_top] = elem;
}

template<typename T,int Size>
void Stack<T,Size>::pop()
{
    if(empty())
    {
        cout << "empty stack" << endl;
        return;
    }
    --_top;
}

template<typename T,int Size>
T & Stack<T,Size>::top()
{
    return _arr[_top];
}

template<typename T,int Size>
bool Stack<T,Size>::empty()
{
    return _top == -1;
}

template<typename T,int Size>
bool Stack<T,Size>::full()
{
    return _top == Size-1;
}

链栈

//Stack.h
template<typename T>
typedef struct StackNode
{
    T data;
    struct StackNode * next;
}StackNode, *LinkStackPtr;

template<typename T>
class Stack
{
public:
    Stack();
    void push(const T &);
    void pop();
    T & top();
    bool empty();
private:
    LinkStackPtr _top;
    int _length;
};

//Stack.cc
template<typename T>
Stack<T>::Stack()
:_length(0),
:_top(NULL)
{}

template<typename T>
void Stack<T>::push(const T & data)
{
    LinkStackPtr p = (LinkStackPtr)malloc(sizeof(StackNode));
    q->data= data;
    q->next = _top;
    _top = q;
    ++_length;
}

template<typename T>
void Stack<T>::pop()
{
    if(empty())
    {
        cout << "empty stack" << endl;
        return;
    }
    LinkStackPtr p = _top;
    _top = p->next;
    free(_top);
    --_length;
}

template<typename T>
T & Stack<T>::top()
{
    return _top->data;
}

template<typename T>
bool Stack<T>::empty()
{
    return _length == 0;
}

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