rotate list

 1 class Solution {
 2 public:
 3     ListNode *rotateRight(ListNode *head, int k) {
 4         // Start typing your C/C++ solution below
 5         // DO NOT write int main() function
 6         if( head == NULL ) return head;
 7         ListNode * root= new ListNode(-1);
 8         root->next = head;
 9         while( k>0 )
10         {
11             k--;
12             head=head->next;
13             if( head == NULL )
14                 head = root->next;
15         }
16         ListNode * p1 = root->next;
17         while( head->next!= NULL )
18         {
19             p1 = p1->next;
20             head = head -> next;
21         }
22         if( p1->next == NULL ) return root -> next;
23         ListNode * tmp = root->next;
24         root->next = p1->next;
25         p1 -> next = NULL;
26         head -> next = tmp;
27         return root->next;      
28     }
29 };

 

posted on 2013-07-04 14:33  jumping_grass  阅读(121)  评论(0)    收藏  举报

导航