[LeetCode] 83. Remove Duplicates from Sorted List

题目链接：传送门

Description

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.

Solution

题意：

去掉有序链表中的重复元素

思路：

直接扫一遍处理

/**
 * 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)  return head;
        ListNode *p = head, *q, *r;
        while (p != NULL) {
            q = p->next;
            while (q && q->val == p->val) {
                r = q;
                q = q->next;
                free(r);
            }
            p->next = q;
            p = q;
        }
        return head;
    }
};