双向链表

双向链表的定义

typedef int DataPyte;
typedef struct DNode
{
	struct DNode* _next; 
	struct DNode* _pPre; 
	DataPyte data;
}DNode, *pDNode, DList, *pDList;

创建一个新结点

pDNode BuyNode(DataPyte d)
{
	pDNode pdnode = (pDNode)malloc(sizeof(DNode));
	if (NULL == pdnode)
	{
		assert(0);
	}
	pdnode->data = d;
	pdnode->_next = NULL;
	pdnode->_pPre = NULL;
	return pdnode;
}

初始化

void DListInit(pDList* ppdlist)
{
	assert(ppdlist);
	pDNode pdnode = BuyNode(0);
	pdnode->_next = pdnode;
	pdnode->_pPre = pdnode;
	*ppdlist = pdnode;
}

尾部插入

void DListPushBack(pDList pdlist, DataPyte d)
{
	assert(pdlist);
	pDNode pdnode = BuyNode(d);
	pDNode cur = pdlist;
	while (pdlist != cur->_next)
	{
		cur = cur->_next;
	}
	pdnode->_pPre = cur;
	pdnode->_next = cur->_next;
	cur->_next->_pPre = pdnode;
	cur->_next = pdnode;
}

尾部删除

void DListPopBack(pDList pdlist)
{
	assert(pdlist);
	if (pdlist->_next == pdlist)
	{
		return;
	}
	pDNode cur = pdlist;
	while (pdlist != cur->_next)
	{
		cur = cur->_next;
	}
	cur->_next->_pPre = cur->_pPre;
	cur->_pPre->_next = cur->_next;
	free(cur);
	cur = NULL;
}

任意位置插入

void DListInsert(pDList pdlist, DataPyte d, DataPyte find)
{
	assert(pdlist);
	pDNode pdnode = BuyNode(d);
	pDNode cur = pdlist;
	while (find != cur->data)
	{
		cur = cur->_next;
	}
	pdnode->_pPre = cur->_pPre;
	pdnode->_next = cur;
	cur->_pPre->_next = pdnode;
	cur->_pPre = pdnode;
}

任意位置删除

void DListDelete(pDList pdlist, DataPyte d)
{
	assert(pdlist);
	pDNode cur = pdlist;
	while (d != cur->data)
	{
		cur = cur->_next;
	}
	cur->_next->_pPre = cur->_pPre;
	cur->_pPre->_next = cur->_next;
	free(cur);
	cur = NULL;
}

销毁

void DListDestroy(pDList* ppdlist)
{
	assert(ppdlist);
	pDNode cur = (*ppdlist)->_next;
	while ((*ppdlist) != cur)
	{
		pDNode del = cur;
		cur = cur->_next;
		free(del);
		del = NULL;
	}
	cur = NULL;
	free(*ppdlist);
	*ppdlist = NULL;
}