leetcode Reverse Linked List II

不说了，贴代码

class Solution {
public:
    ListNode *reverseBetween(ListNode *head, int m, int n)
    {
       if(head==NULL)return NULL;
       ListNode *p=head;
       int i=1;
       for(;i<m;i++)
       p=p->next;
       for(int j=m;j<n;j++)
       {
           ListNode *q=p;
           for(int k=j;k<n;k++)
           {
               q=q->next;
           }
           swap(p->val,q->val);
           n--;
           p=p->next;
       }
       return head;
    }
};