算法题目---从尾到头打印链表

来源：互联网发布：linux怎么粘贴编辑：程序博客网时间：2024/06/07 05:28

输入一个链表的头结点，从尾到头反过来打印出每个结点的值。

#include<iostream>

#include<stdio.h>
#include<stdlib.h>
#include<stack>

using namespace std;

struct ListNode
{
int m_nValue;
ListNode *m_pNext;

};

//采用栈方法
void PrintListReversingly_Iteratively(ListNode *pHead)
{
   stack<ListNode*>nodes;

   ListNode *pNode = pHead;

   while(pNode != NULL)
   {
       nodes.push(pNode);
       pNode = pNode->m_pNext;
   }

   while(!nodes.empty())
   {
       pNode = nodes.top();
       printf("%d\t",pNode->m_nValue);
       nodes.pop();
   }
   printf("\n");
}

//采用递归方法

void PrintListReversingly_Recursively(ListNode *pHead)
{
   if(pHead != NULL)
   {
       if(pHead->m_pNext != NULL)
       {
               PrintListReversingly_Recursively(pHead->m_pNext);
       }
       printf("%d\t",pHead->m_nValue);
   }

}

//尾加结点
void AddToTail(ListNode **pHead,int value)
{
   ListNode *pNew = new ListNode();
   pNew->m_nValue = value;
   pNew->m_pNext = NULL;

   if(*pHead == NULL)
   {
       *pHead = pNew;
   }
   else
   {
       ListNode *pNode = *pHead;

       while(pNode->m_pNext != NULL)
           pNode = pNode->m_pNext;
       pNode->m_pNext = pNew;
   }
}

//删除结点

void RemoveNode(ListNode **pHead,int value)
{
   if(pHead == NULL || *pHead == NULL)
           return;

   ListNode *pToBeDeleted = NULL;
   if((*pHead)->m_nValue == value)
   {
       pToBeDeleted = *pHead;
       *pHead = (*pHead)->m_pNext;
   }
   else
   {
       ListNode *pNode = *pHead;
       while(pNode->m_pNext != NULL && pNode->m_pNext->m_nValue != value)
               pNode = pNode->m_pNext;

       if(pNode->m_pNext != NULL && pNode->m_pNext->m_nValue == value)
       {
           pToBeDeleted = pNode->m_pNext;
           pNode->m_pNext = pNode->m_pNext->m_pNext;
       }
   }

   if(pToBeDeleted != NULL )
   {
       delete pToBeDeleted;
       pToBeDeleted = NULL;
   }
}

void test()
{
       //ListNode *p = (ListNode*)malloc(sizeof(ListNode));
       //ListNode *p;// error
       ListNode *p = NULL;
       AddToTail(&p,1);
       AddToTail(&p,2);
       AddToTail(&p,3);
       AddToTail(&p,4);
       AddToTail(&p,5);

      PrintListReversingly_Iteratively(p);
       printf("\n");
       RemoveNode(&p,3);
       PrintListReversingly_Recursively(p);
       printf("\n");
}

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