LeetCode--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.

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution 
{
public:
    ListNode *deleteDuplicates(ListNode *head) 
    {
        if(head == NULL || head->next == NULL)
            return head;
        ListNode* pre = head;
        ListNode* end = head->next;
        while(end!=NULL)
        {
            if(pre->val != end->val)
            {
                pre->next = end;
                pre = end;
            }
            end = end->next;
        }
        pre->next = NULL;
        return head;
    }
};

LeetCode--Remove Duplicates from Sorted List

原文：http://blog.csdn.net/shaya118/article/details/42676409