C++数据结构之链式队列

链式队列：用链表做的队列；先进先出；使用c++模板类

#ifndef QUEUE_H_INCLUDED
#define QUEUE_H_INCLUDED

template <class Object>
class Queue
{
public:
    Queue();
    ~Queue();
    bool IsEmpty() const;
    const Object & getFront() const;//返回队首数据
    void enqueue(const Object &x);//入队
    Object dequeue();//删除
    void makeEmpty();

private:
    struct QueueNode
    {
        Object element;
        QueueNode *next;

        QueueNode(const Object & theElement,QueueNode *n = 0):element(theElement),next(n){}
    };
    QueueNode *front;
    QueueNode *back;

};

template <class Object>
Queue<Object>::Queue()
{
    front = back = 0;
}

template <class Object>
Queue<Object>::~Queue()
{
    makeEmpty();
}

template <class Object>
void Queue<Object>::makeEmpty()
{
    while(!IsEmpty())
        dequeue();

}

template <class Object>
bool Queue<Object>::IsEmpty() const
{
    return front == 0;
}

template <class Object>
const Object & Queue<Object>::getFront() const
{
    if(IsEmpty())
        throw "Queue is empty";
    return front->element;
}

template <class Object>
void Queue<Object>::enqueue(const Object &x)
{
    if(IsEmpty())
        back = front = new QueueNode(x);
    else
        back = back->next = new QueueNode(x);
}

template<class Object>
Object Queue<Object>::dequeue()
{
    Object frontItem = getFront();

    QueueNode *old;
    old = front;
    front = front->next;
    delete old;
    return frontItem;

}
#endif // QUEUE_H_INCLUDED

#include 
#include "Queue.h"
using namespace std;

int main()
{
    Queue<int> myQ;

    myQ.enqueue(10);
    myQ.enqueue(20);
    myQ.enqueue(30);
    cout << myQ.getFront()<<endl;
    myQ.dequeue();
    cout << myQ.getFront()<<endl;

    for(int j = 0; j < 8;j++)
    {
        for(int i = 0;i<8;i++)
            myQ.enqueue(i);
        while(!myQ.IsEmpty())
            cout << myQ.dequeue()<<endl;
    }

    return 0;
}