1 #include "stdafx.h" 2 #include <iostream> 3 /* 4 题目:在O(1)时间删除链表结点 5 给定单向链表的头指针和一个结点指针，定义一个函数在O(1)时间删除该结点。链表结点与函数定义如下: 6 struct ListNode 7 { 8 int m_nValue; 9 ListNode *m_pNext; 10 }; 11 void DeleteNode(ListNode** pListHead,ListNode* pToBeDeleted); 12 */ 13 using namespace std; 14 struct ListNode 15 { 16 int m_nValue; 17 ListNode *m_pNext; 18 }; 19 void DeleteNode(ListNode** pListHead,ListNode* pToBeDeleted) 20 { 21 if (pListHead ==NULL||pToBeDeleted==NULL) 22 { 23 return; 24 } 25 //删除的不是尾结点 26 if(pToBeDeleted->m_pNext!=NULL) 27 { 28 ListNode* pNext = pToBeDeleted->m_pNext; 29 pToBeDeleted->m_nValue=pNext->m_nValue; 30 pToBeDeleted->m_pNext=pNext->m_pNext; 31 delete pNext; 32 pNext=NULL; 33 } 34 //链表只有一个结点 35 else if(*pListHead==pToBeDeleted) 36 { 37 delete pToBeDeleted; 38 pToBeDeleted=NULL; 39 *pListHead = NULL; 40 } 41 //如果要删除的是尾结点 42 else 43 { 44 ListNode* pNode = *pListHead; 45 while(pNode->m_pNext!=pToBeDeleted) 46 pNode=pNode->m_pNext; 47 pNode->m_pNext = NULL; 48 delete pToBeDeleted; 49 pToBeDeleted=NULL; 50 } 51 } 52 53 54 int _tmain(int argc, _TCHAR* argv[]) 55 { 56 57 return 0 ; 58 }