#include <iostream>

#include <Windows.h>

using namespace std;

#define MAXSIZE 6

typedef int QElemType;

typedef struct {

    QElemType* base;//基地址

    int rear;//尾指针

    int front;//头指针

}LoopQueue;

//初始化循环队列

bool InitList(LoopQueue &queue) {

    queue.base = new int[MAXSIZE];

    if (!queue.base)return false;

    queue.front = queue.rear = 0;

    return true;

}

//入队

bool InsertQueue(LoopQueue& queue, QElemType e) {

    if ((queue.rear + 1) % MAXSIZE == queue.front) {

        cout << "队列已满，无法入队！" << endl;

        return false;

    }

    queue.base[queue.rear] = e;

    queue.rear = (queue.rear + 1) % MAXSIZE;

    return true;

}

//打印队列

bool PrintQueue(LoopQueue& queue) {

    if (queue.front == queue.rear) {

        cout << "队列为空，无法打印队列！" << endl;

        return false;

    }

    int i = queue.front;

    while (queue.front != queue.rear && (i + MAXSIZE) % MAXSIZE != queue.rear)

    {

        cout << queue.base[i] << " ";

        i++;

    }

    cout << endl;

    return true;

}

//获取头结点

int getHead(LoopQueue& queue) {

    return queue.base[queue.front];

}

//获取尾结点

int getBack(LoopQueue& queue) {

    return queue.base[queue.rear-1];

}

//获取队列的长度

int getLength(LoopQueue& queue) {

    return (queue.rear - queue.front + MAXSIZE) % MAXSIZE;

}

//出队

bool DeleteQueue(LoopQueue& queue, QElemType&e) {

    if (queue.front == queue.rear) {

        cout << "队列为空，无法出队！" << endl;

        return false;

    }

    e = queue.base[queue.front];

    queue.front = (queue.front + 1) % MAXSIZE;

    return true;

}

//销毁队列

void DestroyQueue(LoopQueue& queue) {

    if (queue.base) {

        delete queue.base;

    }

    queue.base = NULL;

    queue.front = queue.rear = 0;

}

//清空队列

void ClearQueue(LoopQueue& queue) {

    queue.front = queue.rear = 0;

}

void show_menu() {

    cout << "----------------循环队列的基本操作--------------\t" << endl;

    cout << "\t\t1.初始化循环队列" << endl;

    cout << "\t\t2.入队" << endl;

    cout << "\t\t3.获取队列的头结点" << endl;

    cout << "\t\t4.获取队列的尾结点" << endl;

    cout << "\t\t5.获取队列的长度" << endl;

    cout << "\t\t6.出队" << endl;

    cout << "\t\t7.打印队列" << endl;

    cout << "\t\t8.清空队列" << endl;

    cout << "\t\t0.退出系统" << endl;

}

int main() {

    LoopQueue queue;

    int  choose = -1;

    bool flag = -1;

    int e = 0;

    int elem = 0;

    show_menu();

    while (flag) {

        cout << "请选择：";

        cin >> choose;

        switch (choose)

        {

        case 1:

            if (InitList(queue)) {

                cout << "队列初始化成功！" << endl;

                break;

            }

            else {

                cout << "队列初始化失败！" << endl;

                break;

            }

        case 2:

            cout << "请输入要插入的元素：";

            cin >> e;

            if (InsertQueue(queue, e)) {

                cout << "元素 " << e << " 插入成功！" << endl;

                break;

            }

            else {

                cout << "元素 " << e << " 插入失败！" << endl;

                break;

            }

        case 3:

            cout << "队列的头结点为：" << getHead(queue) << endl;

            break;

        case 4:

            cout << "队列的尾结点为：" << getBack(queue) << endl;

            break;

        case 5:

            cout << "队列的长度为：" << getLength(queue) << endl;

            break;

        case 6:

            if (DeleteQueue(queue, elem)) {

                cout << "元素 " << elem << " 出队成功！" << endl;

                break;

            }

            else {

                cout << "元素出队失败！" << endl;

                break;

            }

        case 7:

            PrintQueue(queue);//打印队列

            break;

        case 8:

            ClearQueue(queue);

            cout << "清空队列元素！" << endl;

            break;

        default:

            flag = 0;

        }

    }

    DestroyQueue(queue);//销毁队列

    system("pause");

    return 0;

}