循环队列的实现（C语言）

/*循环队列VS2010 调试*/#include <stdio.h>#include <malloc.h>#include <stdlib.h>#define MAX_SIZE 6#define TRUE 1#define FALSE 0#define OVERFLOW 0#define OK 1#define ERROR 0typedef struct seq_queue{int front;int rear;int *data;}sq;/*函数功能：初始化循环队列*/int init_seq_queue(sq *Q){Q->data = (int *)malloc(MAX_SIZE * sizeof(int));if(!Q->data){return ERROR;}Q->front = 0;Q->rear = 0;return OK;}/*函数功能：队列元素是否为空返 回 值：1 为空； 0 非空*/int is_queue_empty(sq Q){return ((Q.front == Q.rear) ? TRUE : FALSE);}/*函数功能：队列是否已满返 回 值：1 已满； 0 未满*/int is_queue_full(sq Q){return (((Q.rear+1) % MAX_SIZE == Q.front) ? TRUE : FALSE);}/*函数功能：元素num入队*/int enqueue(sq *Q, int num){if(is_queue_full(*Q)){return OVERFLOW;}Q->rear = (Q->rear + 1) % MAX_SIZE;Q->data[Q->rear] = num;return OK;}/*函数功能：元素出队，出队元素存入num*/int dequeue(sq *Q, int *num){if(is_queue_empty(*Q)){return ERROR;}Q->front = (Q->front + 1) % MAX_SIZE;*num = Q->data[Q->front];return OK;}/*函数功能：获取队头元素，元素存入num*/int get_elem(sq Q, int *num){if (is_queue_empty(Q)){return ERROR;}*num = Q.data[Q.front + 1];return OK;}/*函数功能：获得队列长度返 回 值：队列长度*/int get_queue_length(sq Q){return ((Q.rear - Q.front) + MAX_SIZE) % MAX_SIZE;}/*函数功能：打印队列元素*/void print_queue(sq Q){int i = Q.front + 1;if(is_queue_empty(Q)){return ;}printf("FRONT<-");while(i != ((Q.rear + 1) % MAX_SIZE)){printf("%d<-", Q.data[i]);i = (i + 1) % MAX_SIZE;}printf("REAR\n");}/*函数功能：销毁队列*/void destory_queue(sq *Q){free(Q->data);}int main(int argc, char *argv[]){int num = 0;sq seq_queue;init_seq_queue(&seq_queue);enqueue(&seq_queue, 4);enqueue(&seq_queue, 5);enqueue(&seq_queue, 6);enqueue(&seq_queue, 7);print_queue(seq_queue);dequeue(&seq_queue, &num);print_queue(seq_queue);enqueue(&seq_queue, 8);print_queue(seq_queue);destory_queue(&seq_queue);return 0;}