基于链表的队列

#include<iostream>

#include<stdexcept>

using  namespace std;

class Lqueue{

public:

    Lqueue():m_rear(NULL),m_front(NULL){}

    ~Lqueue(){

    for(Node *n;m_front;m_front=n)

    {//从前到后析构  当m_front为0时停止

    n=m_front->m_next;

    delete m_front;

    }

    }

    void push(int data){

     

        Node *node=new Node(data,NULL);//这一步完成了对m_data和m_next的初始化   Node(int data=0):m_data(data),m_next(NULL){}

    if(m_rear==NULL)

    {   m_front=node;

        m_rear=node;

     

    }else

        {

        m_rear->m_next=node;

        m_rear=node;

        }

}

 

    int pop(){

if(empty())

throw UnderFlow();

     

    int temp=m_front->m_data;

    m_front=m_front->m_next;

    delete m_front;

    if(!(m_front->m_next))

        m_rear=NULL;

return temp;

    }

 

    bool empty(){

    return !m_front&&!m_rear;

    }

private:

    class Node{

    public:

        Node(int data=0,Node *next=NULL):m_data(data),m_next(next){}

        int m_data;

        Node *m_next;

    };

    class UnderFlow{

        const char*what()const throw(){

        cout<<"队列下溢"<<endl;

        }

    };

    Node *m_rear;//后端

    Node *m_front;//前端

};

 

int main(){

    try{

        Lqueue lqueue;

    for(int i=0;i<10;i++)

        lqueue.push(i);

while(!(lqueue.empty()))

                cout<<lqueue.pop()<<endl;

                cout<<endl;

    }

    catch(exception &ex){

    cout<<ex.what()<<endl;

    }

return 0;

}