ListNode<int>* MergeSortedLists(ListNode<int>* plhsHead, ListNode<int>* prhsHead)
{if (NULL == plhsHead){return prhsHead;}if (NULL == prhsHead){return plhsHead;}ListNode<int>* pMergeHead = NULL;if (plhsHead->m_stData < prhsHead->m_stData){pMergeHead = plhsHead;pMergeHead->m_pNextNode = MergeSortedLists(plhsHead->m_pNextNode, prhsHead);}else{pMergeHead = prhsHead;pMergeHead->m_pNextNode = MergeSortedLists(plhsHead, prhsHead->m_pNextNode);}return pMergeHead;
}// 非递归方法：合并两个有序链表
//时间复杂度：O(n), 时间复杂度(1)
ListNode<int>* MergeSortedLists_1(ListNode<int>* pHead1, ListNode<int>* pHead2)
{if (NULL == pHead1){return pHead2;}if (NULL == pHead2){return pHead1;}// 1.新链表头结点ListNode<int>* pMergeHead = NULL;if (pHead1->m_stData <= pHead2->m_stData){pMergeHead = pHead1;pHead1 = pHead1->m_pNextNode;}else{pMergeHead = pHead2;pHead2 = pHead2->m_pNextNode;}ListNode<int>* pTmpNode = pMergeHead;// 2.比较两个链表，较小的节点加入新链表后面while (pHead1 && pHead2){if (pHead1->m_stData <= pHead2->m_stData){pTmpNode = pHead1;pHead1 = pHead1->m_pNextNode;}else{pTmpNode = pHead2;pHead2 = pHead2->m_pNextNode;}// 不能让新链表中断！！！！if (NULL != pTmpNode->m_pNextNode){pTmpNode = pTmpNode->m_pNextNode;}}// 3.链接剩余的元素if (pHead1 && pTmpNode){pTmpNode->m_pNextNode = pHead1;}if (pHead2 && pTmpNode){pTmpNode->m_pNextNode = pHead2;}return pMergeHead;
}void MergeSortedListsTestFunc()
{cout << "\n\n --------------- MergeSortedListsTestFunc Start -------------->" << endl;// 初始化链表1int aiArray[] = {1, 2, 3, 4, 5, 6, 7, 8};int iLen = sizeof(aiArray) / sizeof(int);TRAVERSAL_ARRAY(aiArray, iLen);CSingleList<int>* pList = new CSingleList<int>();if (!pList){return;}for (int i = 0; i < iLen; i++){pList->Insert(aiArray[i]);}pList->Traversal();// 初始化链表2int aiArray2[] = {9, 10, 11, 12, 13, 14, 15};int iLen2 = sizeof(aiArray2) / sizeof(int);TRAVERSAL_ARRAY(aiArray2, iLen2);CSingleList<int>* pList2 = new CSingleList<int>();if (!pList2){SAVE_DELETE(pList);return;}for (int i = 0; i < iLen2; i++){pList2->Insert(aiArray2[i]);}pList2->Traversal();ListNode<int>* pHead1 = pList->GetHeadNode();ListNode<int>* pHead2 = pList2->GetHeadNode();// 合并链表//ListNode<int>* pMergeNode = MergeSortedLists(pHead1, pHead2);//if (pMergeNode)//{//    cout << "两个有序链表合并后: " << endl;//    TraversalList(pMergeNode);//}//cout << "合并后原来链表值: " << endl;//pList->Traversal();//pList2->Traversal();
    ListNode<int>* pMergeNode = MergeSortedLists_1(pHead1, pHead2);if (pMergeNode){cout << "两个有序链表合并后: " << endl;TraversalList(pMergeNode);}// 释放内存
    SAVE_DELETE(pList);// list 与 pList2 已经合并在一起，不用重复释放pLIst2!!!!//SAVE_DELETE(pList2);
cout << "\n\n --------------- MergeSortedListsTestFunc End -------------->" << endl;}