循环队列实现

queue.h

#ifndef QUEUE_
#define QUEUE_

#define SIZE 10

typedef int data_t;

typedef struct head{
        data_t data[SIZE];
        int front;
        int rear;
}queue_t;

queue_t *queue_creat();

int queue_is_empty(queue_t *head);

int queue_is_full(queue_t *head);

void queue_clear(queue_t *head);

int queue_en(queue_t *head,data_t data);

data_t queue_de(queue_t *head);

void queue_show(queue_t *head);

void queue_detory(queue_t **head);

#endif

queue.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <strings.h>

#include "queue.h"


queue_t *queue_creat()
{
        queue_t *head = (queue_t *)malloc(sizeof(queue_t));
        bzero(head,sizeof(queue_t));

        head->front = 0;
        head->rear = 0;

        return head;
}

int queue_is_empty(queue_t *head)
{
        return head->front == head->rear;
}

int queue_is_full(queue_t *head)
{
        return head->rear - head->front == SIZE;
}

void queue_clear(queue_t *head)
{
        head->rear = head->front;
}

int queue_en(queue_t *head,data_t data)
{
        if(queue_is_full(head))
        {
                printf("queue is fulll\n");
                return -1;
        }

        head->data[head->rear%SIZE] = data;
        head->rear++;

        return 0;
}

data_t queue_de(queue_t *head)
{
        if(queue_is_empty(head))
        {
                printf("queue is empty\n");
                return -1;
        }

        data_t data = head->data[head->front%SIZE];
        head->front++;

        return data;
}

void queue_show(queue_t *head)
{
        int i;
        for(i=head->front;i<head->rear;i++)
        {
                printf("%d\t",head->data[i%SIZE]);
        }
        printf("\n");
}

void queue_destory(queue_t **head)
{
        free(*head);
        *head = NULL;
 }       

main.c

#include <stdio.h>

#include "queue.h"

int main()
{
        queue_t *head = queue_creat();

        int n=10;
        while(n--)
        {
                queue_en(head,n+1);
        }

        queue_show(head);
        queue_destory(&head);

        return 0;
}