循环队列的例程

循环队列的例程，大家共同学习 #include <stdio.h> #include <stdlib.h> #include "queue.h" QUEUE QueueCreate(int size) { QUEUE q = (QUEUE)malloc(sizeof(*q)); if(q == NULL) { return NULL; } q->data = (QElement *)malloc(sizeof(QElement) * size); if(q->data == NULL) { free(q); return NULL; } q->capacity = size; QueueMakeEmpty(q); return q; } void QueueMakeEmpty(QUEUE q) { q->size = 0; q->front = 1; q->rear = 0; } int QueueIsEmpty(QUEUE q) { return (q->size == 0); } int QueueIsFull(QUEUE q) { return (q->size == q->capacity); } static int repeat(QUEUE q, int value) { if(++value == q->capacity) value = 0; return value; } int QueueEn(QUEUE q, const QElement *data) { if(QueueIsFull(q)) return -1; q->rear = repeat(q, q->rear); q->data[q->rear] = *data; q->size++; return 0; } int QueueDe(QUEUE q) { if(QueueIsEmpty(q)) return -1; q->front = repeat(q, q->front); q->size--; return 0; } int QueueFront(QUEUE q, QElement *data) { if(QueueIsEmpty(q)) return -1; *data = q->data[q->front]; return 0; } int QueueFrontAndDe(QUEUE q, QElement *data) { if(QueueFront(q, data) == 0) return QueueDe(q); return -1; } void QueueDispose(QUEUE q) { free(q->data); free(q); }