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C++單向連結串列-查詢某個節點

本演算法從下標1開始遍歷 利用雙指標的形式遍歷, 大大提高了程式碼的查詢速度:

ListNode* FindKthToTail(ListNode* pListHead, unsigned int k)
{
	if (pListHead == NULL || k ==0)
	{
		return NULL;
	}
	ListNode* pAhead = pListHead;
	ListNode* pBhead = NULL;
	for (unsigned int i = 0; i < k-1; i++)
	{
		if (pAhead->m_pNext != NULL)
		{
			pAhead = pAhead->m_pNext;
		}
		else
		{
			return NULL;
		}
	}
	pBhead = pListHead;
	while (pAhead->m_pNext != NULL)
	{
		pAhead = pAhead->m_pNext;
		pBhead = pBhead->m_pNext;
	}
	return pBhead;
}

void Test()
{
	printf("stat\n");
	ListNode* pNode1 = CreateListNode(1);
	ListNode* pNode2 = CreateListNode(2);
	ListNode* pNode3 = CreateListNode(3);
	ListNode* pNode4 = CreateListNode(4);
	ListNode* pNode5 = CreateListNode(5);

	CoonnectListNode(pNode1, pNode2);
	CoonnectListNode(pNode2, pNode3);
	CoonnectListNode(pNode3, pNode4);
	CoonnectListNode(pNode4, pNode5);
	printf("exepectd result:4\n");
	ListNode* pNode = FindKthToTail(pNode1, 1);
	PrintListNode(pNode);
	DestroyList(pNode1);

}