递归实现单链表的逆转

#include <stdio.h>

struct Node{
    int data;
    Node *next;
public:
    Node()
    {
        Node(0,NULL);
    }

    Node(int data)
    {
        Node(data,NULL);
    }

    Node(int data,Node *next)
    {
        this->data=data;
        this->next=next;
    }
};

Node* CreList(int size)
{
    Node* p;
    Node* pPre;
    for (int i=0;i<size;i++)
    {
        pPre=p;
        p=new Node(size-i,(i==0)?NULL:pPre);
    }
    return p;
}

void Print(Node* p)
{
    while (p!=NULL)
    {
        printf("%d,",p->data);
        p=p->next;
    }
    printf("\n");
}


Node* RevList_Bak(Node *head , Node* pre)//C面试算法解析
{//递归实现单链表的逆转
    Node* p = head->next;//数据位置不动，单纯改变指针的指向，方向
    head->next = pre;
    pre = head;
    
    if(p) return RevList_Bak(p,pre);
    
    else return head;
}




Node* RevList(Node *head,Node *pPrev )
{
    Node * pNext;
    if (head->next!=NULL)
    {
       pNext=head->next;
       head->next=pPrev;
       return RevList(pNext,head);      
    }
    else
    {
        head->next=pPrev;
        return head;
    }
}

void main(int argc,char* argv[])
{
    Node*p = CreList(6);
    Print(p);
    
    Node* q = RevList(p,NULL);    
    Print(q);
}
/*
1,2,3,4,5,6,
6,5,4,3,2,1,
Press any key to continue
*/

 

//递归
Node* RevList(Node *head,Node *pPrev )
{
    Node * pNext;
    if (head->next!=NULL)
    {
       pNext=head->next;
       head->next=pPrev;
       return RevList(pNext,head);      
    }
    else
    {
        head->next=pPrev;
        return head;
    }
}

//循环
Node* RevList(Node *head )
{
    Node * pNewList=NULL;
    Node *pOldList=head;

    while (pOldList->next!=NULL)
    {
        Node * pOldListNext=pOldList->next;
        pOldList->next=pNewList;
        pNewList=pOldList;
        pOldList=pOldListNext;
    }
    pOldList->next=pNewList;
    pNewList=pOldList;
    return pNewList;
    
}


void main(int argc,char* argv[])
{
    Node*p = CreList(6);
    Print(p);
    
    //Node* q = RevList(p,NULL);    
    Node* q = RevList(p);
    Print(q);
}
/*
1,2,3,4,5,6,
6,5,4,3,2,1,
Press any key to continue
*/