C例子：队列（链式存储的方式）

/* ************************** * Soure file of Queue * *************************/ #include"Ex020_Queue2.h" //实现Queue的函数，为了方便,放到了主函数所在的文件中，最好是单独建立实现函数的源文件 int QueueInit(Queue *q) { if(NULL == q) return FAILE; q->front = q->rear = NULL; q->size = 0; return SUCCESS; } int QueueDestroy(Queue *q) { QueueNode *temp = NULL; if(NULL == q) return FAILE; if(q->size == 0) { printf("Queue is empty \n"); return SUCCESS; } while(q->size >0) { temp = q->front; q->front = temp->next; temp->next = NULL; free(temp); q->size -= 1; } q->front = q->rear = NULL; return SUCCESS; } int QueuePrint(Queue *q) { QueueNode *temp = NULL; if(NULL == q) return FAILE; if(q->size == 0) { printf("Queue is empty \n"); return SUCCESS; } printf("Elmt of Queue:"); temp = q->front; while(temp != NULL) { printf("%d ",temp->elmt); temp = temp->next; } printf("\n"); return SUCCESS; } int EnQueue(Queue *q,QueueElmt e) { QueueNode *node; if(NULL == q) return FAILE; node = (QueueNode*)malloc(sizeof(QueueNode)); if( NULL != node) { if(q->size == 0) q->front = q->rear = node; else { q->rear->next = node; q->rear = node; } node->elmt = e; node->next = NULL; q->size +=1; return SUCCESS; } else return FAILE; } int DeQueue(Queue *q,QueueElmt *e) { QueueNode * node; if(NULL == q) return FAILE; if(q->size > 0 ) { node = q->front; *e = node->elmt; q->front = node->next; q->size -=1; node->elmt =0; node->next = NULL; free(node); return SUCCESS; } else return FAILE; } int main() { int i = 0; int result =0; QueueElmt e; Queue queue; QueueInit(&queue); QueuePrint(&queue); while(i<5) EnQueue(&queue,(++i)); result = EnQueue(&queue,9); if(FAILE == result) printf("EnQueue is failed \n"); else QueuePrint(&queue); DeQueue(&queue,&e); printf("%d is deleted from Queue \n",e); QueuePrint(&queue); DeQueue(&queue,&e); printf("%d is deleted from Queue \n",e); QueuePrint(&queue); DeQueue(&queue,&e); printf("%d is deleted from Queue \n",e); QueuePrint(&queue); DeQueue(&queue,&e); printf("%d is deleted from Queue \n",e); QueuePrint(&queue); DeQueue(&queue,&e); printf("%d is deleted from Queue \n",e); QueuePrint(&queue); DeQueue(&queue,&e); printf("%d is deleted from Queue \n",e); QueuePrint(&queue); result = DeQueue(&queue,&e); if(FAILE == result) printf("DeQueue is failed \n"); QueueDestroy(&queue); QueuePrint(&queue); return result; }