数据结构和算法学习总结03 线性表---队列

#include <iostream>  
using namespace std;  

struct Node  
{  
    int data;  
    struct Node *next;  
};  

class Queue  
{  
public:  
    Queue( )               //构造函数，初始化一个空的链队列  
    {
        Node *s;  
        s=new Node;  
        s->next=NULL;  
        front=rear=s; 
    }
    ~Queue( )               //析构函数，释放链队列中各结点的存储空间  
    { 
        while(front)
        {    Node *p;  
        p=front->next;  
        delete front;  
        front=p;} 
    }  
    
    void EnQueue(int v);   //将元素x入队  
    int DeQueue();         //将队头元素出队  
    int GetQueue();        //取链队列的队头元素  
    bool IsEmpty( );         //判断链队列是否为空 
    
    void Intput(int n);
    void Output();
private:  
    Node *front, *rear;    //队头和队尾指针，分别指向头结点和终端结点  
};   


void Queue::EnQueue(int v)  
{  
    Node *s;  
    s=new Node;   
    s->data=v;          //申请一个数据域为x的结点s  
    s->next=NULL;  
    rear->next=s;       //将结点s插入到队尾  
    rear=s;  
}  

int Queue::DeQueue()  
{      
    Node *p; int x;  
    if (rear==front) cout<<"Null"<<endl;
    p=front->next;   
    x=p->data;                       //暂存队头元素  
    front->next=p->next;             //将队头元素所在结点摘链  
    if (p->next==NULL) 
        rear=front;                     //判断出队前队列长度是否为1  
    delete p;  
    return x;  
}    

int Queue::GetQueue()  
{  
    if (front!=rear)   
        return front->next->data;  
}  

bool Queue::IsEmpty( )  
{  
    if(front==rear)   
        return 1;  
    else   
        return 0;  
} 

void Queue::Intput(int n)
{
    int v;
    for(int i =0; i<n; i++)
    {
        cout<<"请输入元素的值:"<<endl;
        cin>>v;
        EnQueue(v);
    }
}

void Queue::Output()
{
    Node *p;
    p = front;
    while(p!=rear)
    {
        p=p->next;
        cout<<p->data<<" ";    
    }
    cout<<endl;
}   

int main()
{
    Queue l;
    cout<<l.IsEmpty()<<endl;
    l.Intput(5);
    cout<<l.IsEmpty()<<endl;
    l.Output();
    l.EnQueue(6);
    l.DeQueue();
    l.Output();
}