循环队列

#include "stdafx.h"
#include<iostream>

using namespace std;
#define MAXQSIZE 100
typedef int QElemType;

typedef enum Status {
    success, fail, fatal, rangeerror, overflow
}Status;

typedef struct {
    QElemType *base;//初始化动态分配存储空间
    int front;
    int rear;
}SqQueue;

Status InitQueue(SqQueue &q) {
    q.base = (QElemType*)malloc(MAXQSIZE * sizeof(QElemType));
    if (q.base == NULL) exit(OVERFLOW);
    q.rear = q.front = 0;
    return success;
}

int QueueLength(SqQueue q) {
    return (q.rear - q.front+ MAXQSIZE)% MAXQSIZE;
}

Status EnQueue(SqQueue &q, QElemType elem) {
    if ((q.rear + 1) % MAXQSIZE == q.front) return overflow;
    q.base[q.rear] = elem;
    q.rear = (q.rear + 1) % MAXQSIZE;
    return success;
}

Status DeQueue(SqQueue &q, QElemType &elem) {
    if (q.rear == q.front) return fail;
    elem = q.base[q.front];
    q.front = (q.front + 1) % MAXQSIZE;
    return success;
}

void PrintQueue(SqQueue q) {
    
    for(int i=q.front;i<q.rear;i++)
    {
        cout << q.base[i] << " ";
    }
    cout << endl;
}

int main() {
    SqQueue q;
    InitQueue(q);
    int arr[] = { 2,5,3,7 };
    int len = sizeof(arr) / sizeof(arr[0]);
    for (int i = 0; i < len; i++) {
        EnQueue(q, arr[i]);
    }
    PrintQueue(q);
    QElemType elem;
    DeQueue(q, elem);
    cout << "删除的元素为：" << elem <<endl;
    system("pause");
    return 0;
}