合并有序链表

ListNode* mergeList(ListNode* pHead1, ListNode* pHead2){if (pHead1 == NULL){return pHead2;}else if (pHead2 == NULL){return pHead1;}ListNode* pMergeHead = NULL;if (pHead1->m_nValue <= pHead2->m_nValue){pMergeHead = pHead1;pMergeHead->m_pNext = mergeList(pHead1->m_pNext, pHead2);}else{pMergeHead = pHead2;pMergeHead->m_pNext = mergeList(pHead1, pHead2->m_pNext);}return pMergeHead;}