// 先分析   拆成三段    16ms 过大的  1 /** 2  * Definition for singly-linked list. 3  * struct ListNode { 4  *     int val; 5  *     ListNode *next; 6  *     ListNode(int x) : val(x), next(NULL) {} 7  * }; 8  */ 9 class Solution {10 public:11     ListNode *reverseBetween(ListNode *head, int m, int n) {12         // Start typing your C/C++ solution below13         // DO NOT write int main() function14         ListNode*preHead,*preEnd,*midHead,*midEnd,*r,*p,*q,*re;15         16         int i;17         18         19         preEnd=NULL;20         p=head;21         22         for(i=0;i
     
      next;26         }27         28         midEnd=p;29         30         q=NULL;31         32         for(i=0;i
      
       next;35             p->next=q;36             q=p;37             p=r;38         }39         40         if(preEnd==NULL)41         {42             re=q;43         }44         else45         {46             re=head;47             preEnd->next=q;48         }49         midEnd->next=r;50         51         return re;52         53         54         55         56         57         58         59     }60     61     62 };