1 class Solution {
2 public:
3 ListNode *deleteDuplicates(ListNode *head) {
4 // IMPORTANT: Please reset any member data you declared, as
5 // the same Solution instance will be reused for each test case.
6 if (head==NULL)
7 return head;
8 ListNode * curHead = head, *curTail = head, *lastTail=NULL;
9 ListNode * itr = head->next;
10 while (itr!=NULL){
11 ListNode * nextNode = itr->next;
12 if (itr->val == curTail->val)
13 curTail = curTail->next;
14 else{
15 if (curHead!=curTail){
16 if (curHead==head){
17 head = itr;
18 }
19 else lastTail->next = itr;
20 }
21 else lastTail = curTail;
22 curHead = curTail = itr;
23 }
24 itr = nextNode;
25 }
26 if (curHead != curTail){
27 if (curHead == head)
28 return NULL;
29 else lastTail->next = NULL;
30 }
31 return head;
32 }
33 };
