数据结构-链队

#include <iostream>
#include <stdlib.h>

using namespace std;

typedef struct QNode
{
    int data;
    struct QNode *next;
}QNode; //队结点
typedef struct
{
    QNode *front;
    QNode *rear;
}LiQueue;//链队类型

void InitQueue(LiQueue *&Q)
{
    Q=(LiQueue*)malloc(sizeof(LiQueue));
    Q->front=Q->rear=NULL;
}

int IsEmpty(LiQueue *Q)
{
    if(Q->front==NULL||Q->rear==NULL)
        return 1;
    else
        return 0;
}

void EnQueue(LiQueue *Q,int e)
{
    QNode *p;
    p=(QNode*)malloc(sizeof(QNode));
    p->data=e;
    p->next=NULL;

    if(Q->rear==NULL)
        Q->front=Q->rear=p;
    else
    {
        Q->rear->next=p;
        Q->rear=p;
    }
}

int DeQueue(LiQueue *Q,int &e)
{
    QNode *p;
    if(Q->rear==NULL)
        return 0;
    else
        p=Q->front;

    if(Q->front==Q->rear)
        Q->front=Q->rear=NULL;
    else
        Q->front=Q->front->next;
    e=p->data;
    free(p);
    return 1;
}

int Print(LiQueue *Q)
{
    if(Q->front==NULL||Q->rear==NULL)
    {
        cout<<"
队空！
";
        return 0;
    }

    QNode *p;
    p=Q->front;
    cout<<"队中元素依次为：
";
    while(p!=Q->rear)
    {
        cout<<"  "<<p->data<<"  ";
        p=p->next;
    }
    cout<<"  "<<p->data<<"  ";
    return 1;
}

int main()
{
    int i,e;
    LiQueue *Q;
    InitQueue(Q);
    for(i=0;i<10;++i)
        EnQueue(Q,i);
    if(IsEmpty(Q)==1)
        cout<<"
队空！
";
    else
        cout<<"
队非空！
";
    Print(Q);
    cout<<"
--------------------------------
";
    cout<<"依次出队3个元素为：
";
    for(i=0;i<3;++i)
    {
        DeQueue(Q,e);
        cout<<"  "<<e<<"  ";
    }
    if(IsEmpty(Q)==1)
        cout<<"
队空！
";
    else
        cout<<"
队非空！
";
    Print(Q);
    cout<<"
--------------------------------
";

    return 0;
}