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) {        ListNode *node, *temp;        if (head == NULL) {            return head;        }                node = head;        while (node) {            if (!node->next) {                return head;            } else {                temp = node->next;                while (node->val == temp->val) {                    node->next = temp->next;                    delete temp;                    temp = node->next;                    if (temp == NULL) {                        return head;                    }                }            }            node = node->next;        }        return head;    }};