LeetCode 刷题： 删除已排序链表中的重复节点

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.

一种解法：

/**
 * 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 *current = head;
        while(current)
        {
            while(current->next && current->val == current->next->val)
            {
                current->next = current->next->next;
            }
            current = current->next;     //Remember, this is a sorted link list
        }
        return head;
    }
};