Remove Duplicates from Sorted List

Given a sorted linked list, delete all duplicates such that each element appear only once.

For example,
Given 1->1->2, return 1->2.
Given 1->1->2->3->3, return 1->2->3.

分析：和Remove Duplicated from Sorted Array类似。运行时间19ms

 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* deleteDuplicates(ListNode* head) {
12         if(!head || !(head->next)) return head;
13         
14         ListNode *temp = head;
15         ListNode *newHead = head;
16         
17         while(temp->next){
18             if(temp->val != temp->next->val){
19                 head->next = temp->next;
20                 head = head->next;
21             }
22             temp = temp->next;
23         }
24         head->next = NULL;
25         return newHead;
26     }
27 };

 

Runtime: 16ms

 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* deleteDuplicates(ListNode* head) {
12         if(!head || !head->next) return head;
13         
14         ListNode* temp = head;
15         while(temp->next){
16             if(temp->val == temp->next->val)
17                 temp->next = temp->next->next;
18             else 
19                 temp = temp->next;
20         }
21         return head;
22     }
23 };
posted @ 2015-04-28 16:39  amazingzoe  阅读(105)  评论(0)  编辑  收藏  举报