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.

题意：去除链表中的重复元素。

思路：直接实现。

struct ListNode {     int val;     ListNode *next;     ListNode(int x) : val(x), next(NULL) {}};class Solution {public:ListNode* deleteDuplicates(ListNode* head) {if (!head)return head;ListNode* p = head;ListNode* q = head->next;int val = head->val;while (q){if (q->val == val){p->next = q->next;free(q);q = p->next;}else{val = q->val;p = p->next;q = q->next;}}return head;}};