5.C-数据结构-二叉树

#include "linkqueue.h" #include <stdio.h> #include <stdlib.h> #include <string.h> /* * queue_create:创建一个空队列 * @ret NULL--err other--空队列指针 * */ linkqueue* queue_create(void){ linkqueue* pQueue = NULL; linklist pLink = NULL; //1.申请空间 //1.1 队列空间 pQueue = (linkqueue*)malloc(sizeof(linkqueue)); if(pQueue == NULL){ printf("pQueue malloc err\n"); return NULL; } //1.2 单链表空间 pLink = (linklist)malloc(sizeof(listnode)); if(pLink == NULL){ printf("pLink malloc err\n"); free(pQueue);//释放前面申请的空间 return NULL; } //2.初始化 pLink->data = 0; pLink->pNext = NULL; pQueue->front = pLink; pQueue->rear = pLink; return pQueue; } /* * enter_queue:入队列 * param pQueue:队列地址 * param value:入队数据 * @ret -1--err 0--success * */ int enter_queue(linkqueue* pQueue,data_t value){ linklist pLink = NULL; //1.判断参数有效性 if(pQueue == NULL){ printf("pQueue is NULL\n"); return -1; } //2.创建链表结点 pLink = (linklist)malloc(sizeof(listnode)); if(pLink == NULL){ printf("malloc err\n"); return -1; } pLink->data = value; pLink->pNext = NULL; //3.入队列 //rear后链接新结点 pQueue->rear->pNext = pLink; //队列指针偏移 pQueue->rear = pLink; return 0; } /* * out_queue:出队列 * param pQueue:队列地址 * param value:出队数据存放的地址 * @ret -1--err 0--success * */ int out_queue(linkqueue* pQueue,data_t* value){ linklist pTmp = NULL; //1.判断参数有效性 if(pQueue == NULL){ printf("pQueue is NULL\n"); return -1; } //2.判断是否为空队列 if(pQueue->front == pQueue->rear){ printf("queue is empty\n"); return -1; } //3.保存剩余数据 pTmp = pQueue->front->pNext->pNext; //4.出队后队列为空时，需将rear指向冗余头部代表空队列 if(pQueue->front->pNext == pQueue->rear){ pQueue->rear = pQueue->front; } //5.开始出队列 *value = pQueue->front->pNext->data; free(pQueue->front->pNext); pQueue->front->pNext = pTmp; return 0; } /* * queue_delete:删除整个队列 * param pQueue:队列地址 * @ret -1--err 0--success * */ int queue_delete(linkqueue** pQueue){ linklist pTmp = NULL; //1.判断参数有效性 if(*pQueue == NULL){ printf("pQueue is NULL\n"); return -1; } //2.开始释放链表 while((*pQueue)->front != NULL){ pTmp = (*pQueue)->front; (*pQueue)->front = (*pQueue)->front->pNext; free(pTmp); } //3.释放队列 free(*pQueue); *pQueue = NULL; return 0; }