leetcode 83

83. 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.

这道题比较简单，去除链表中重复的数。

代码如下：

/**
 * 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* h = head;
        ListNode* l = head->next;
        while(l != NULL)
        {
            if(h->val == l->val)
            {
                l = l->next;
                if(l == NULL)
                {
                    h->next = NULL;
                }
            }
            else
            {
                h->next = l;
                h = h->next;
                l = l->next;
            }
        }
        return head;
    }
};