Data Structure 체인 대기 열 (하나)

//   
#include 
#include 
#include 
using namespace std;

//     
//    
typedef struct QNode
{
    int data;
    struct QNode *next;
}QNode,*QueuePtr;

typedef struct LinkQueue
{
    //      
    QueuePtr front;
    //      
    QueuePtr rear;
}LinkQueue;
//   
void InitQueue_L(LinkQueue &Q)
{
	QueuePtr p=new QNode;
	p->next=NULL;
    Q.front=Q.rear=p;
}
//    
void DestroyQueue_L(LinkQueue &Q)
{
    // Front    
    while(Q.front)
    {
        //        
        //   
        //                
        Q.rear=Q.front->next;
        delete Q.front;
        Q.front=Q.rear;
    }
}
//    
void ClearQueue_L(LinkQueue &Q)
{
    //                 
    //             
    //        
    //         
    //     
    QueuePtr p,q;
    p=Q.front->next;
    while(p)
    {
        q=p;
        p=p->next;
        delete q;
    }
    Q.front->next=NULL;
    Q.rear=Q.front;
}
//     
int QueueLength_L(LinkQueue Q)
{
    QueuePtr p;
    p=Q.front;
    int length;
    length=0;
    while(p->next)
    {
        length++;
        p=p->next;
    }
    return length;
}
//     
void GetHead_L(LinkQueue Q,int &e)
{
    if(Q.front->next==NULL)
    {
        cout<<"The Queue is EMPTY."<<endl;
        return;
    }
    else
    {
        e=Q.front->next->data;
        return;
    }
}
//    
void EnQueue_L(LinkQueue &Q,int &e)
{
    //       
    QueuePtr p;
    p->data=e;
    p->next=NULL;
    //      
    Q.rear->next=p;
    Q.rear=p;
    return;
}
//    
void DeQueue_L(LinkQueue &Q,int &e)
{
    if(Q.front->next==NULL)
    {
        cout<<"The Queue is EMPTY."<<endl;
        return;
    }
    QueuePtr p;
    //p front     
    p=Q.front->next;
    e=p->data;
    Q.front->next=p->next;
    //        
    if(Q.rear==p)
    {
        Q.rear=Q.front;
    }
    delete p;
}


void SeeDoctor()
{
    LinkQueue Q;
//               
    InitQueue_L(Q);			//       Q
    int flag=1;			// flag=1：    ；=0：    
    char ch;
    while(flag)
    {
        cout<<"     ：";
        cin>>ch;
        switch(ch)
        {
            case 'a' :
            case 'A' :
                cout<<"   ：";
                int n;
				cin>>n;
				cout<<endl;
                EnQueue_L(Q,n);//       
                break;
            case 'n' :
            case 'N' :
                if(Q.front->next)
                {
                	int n;
                    DeQueue_L(Q,n); 		//       
                    cout<<"    "<<n<<"     "<<endl;
                }
                else
                    cout<<"       。"<<endl;
                break;
            case 's' :
            case 'S' :
                cout<<"           ：";
                while(Q.front->next)
                {//           
                	int n;
                    DeQueue_L(Q,n);
                    cout<<n<<" ";
                }
                cout<<endl<<"          ！"<<endl;
                flag=0;
                break;
            default:
                cout<<"       ！"<<endl;
        }
    }
} // SeeDoctor
int main()
{
    void SeeDoctor();
    SeeDoctor();
    return 0;
}