[LeetCode] Reverse Linked List II

 1 class Solution {  
 2 public:
 3     ListNode* reverseBetween(ListNode* head, int m, int n) {
 4         ListNode* new_head = new ListNode(0);
 5         new_head -> next = head;
 6         ListNode* pre = new_head;
 7         for (int i = 0; i < m - 1; i++)
 8             pre = pre -> next;
 9         ListNode* cur = pre -> next;
10         for (int i = 0; i < n - m; i++) {
11             ListNode* move = cur -> next; 
12             cur -> next = move -> next;
13             move -> next = pre -> next;
14             pre -> next = move;
15         }
16         return new_head -> next;
17     }
18 };