简单链式队列(C++模版技术实现)
下面代码仅供本人复习数据结构所用,实用性N低,各位飘过吧~~哈哈:>
// // C++ 模版技术实现简单链式队列示例. // #include <cstdlib> #include <iostream> #include <iomanip> #include <stdexcept> // 链式队列类模版前置声明. template <typename T> class LinkedQueue; // // 链式队列节点类模版. // template <typename T> class Node { friend class LinkedQueue<T>; private: T _value; Node<T> *_pNext; public: Node(void) : _pNext(NULL) { NULL; } Node(const T &val) : _value(val) , _pNext(NULL) { NULL; } }; // // 链式队列类模版. // 采用带头节点和尾指针的单向链表. // 当队列为空是尾指针指向头节点. // 入队时从头结点后接入,出队时从尾节点断开. // template <typename T> class LinkedQueue { private: Node<T> *_pFront, *_pRear; public: LinkedQueue(void); ~LinkedQueue(void); bool isEmpty(void) const; size_t getLength(void) const; T getFront(void) const; void enqueue(const T &val); T dequeue(void); }; template <typename T> inline LinkedQueue<T>::LinkedQueue(void) { _pFront = new Node<T>(); _pRear = _pFront; } template <typename T> LinkedQueue<T>::~LinkedQueue(void) { for (Node<T> *pDel = _pFront->_pNext; NULL != pDel; pDel = _pFront->_pNext) { _pFront->_pNext = pDel->_pNext; #if !defined(NDEBUG) std::cout << "删除节点:" << pDel->_value << std::endl; #endif delete pDel; } delete _pFront; } template <typename T> inline bool LinkedQueue<T>::isEmpty(void) const { return _pFront == _pRear; } template <typename T> size_t LinkedQueue<T>::getLength(void) const { size_t len = 0; for (Node<T> *pTemp = _pFront->_pNext; NULL != pTemp; ++len) { pTemp = pTemp->_pNext; } return len; } template <typename T> inline T LinkedQueue<T>::getFront(void) const { return _pFront->_pNext->_value; } template <typename T> inline void LinkedQueue<T>::enqueue(const T &val) { Node<T>* pNew = new Node<T>(val); _pRear->_pNext = pNew; _pRear = pNew; } template <typename T> inline T LinkedQueue<T>::dequeue(void) { if (isEmpty()) { throw std::underflow_error("队空下溢 !"); } Node<T> *pDel = _pFront->_pNext; _pFront->_pNext = pDel->_pNext; T value = pDel->_value; delete pDel; if (NULL == _pFront->_pNext) { _pRear = _pFront; } return value; } // // 队列测试 // int main(void) { LinkedQueue<int> queue; const size_t QUEUE_SIZE = 20; for (size_t i = 0; i < QUEUE_SIZE; ++i) { queue.enqueue(i); } std::cout << std::endl << "队列" << (queue.isEmpty() ? "" : "不") << "为空." << std::endl; for (size_t i = 0; i < QUEUE_SIZE; ++i) { std::cout << std::setw(3) << queue.dequeue(); } // std::cout << std::setw(3) << queue.dequeue(); std::cout << std::endl << "队列" << (queue.isEmpty() ? "" : "不") << "为空." << std::endl; return EXIT_SUCCESS; }