LeetCode 82: Remove Duplicates from Sorted List II

Given a sorted linked list, delete all nodes that have duplicate numbers, leaving onlydistinct numbers from the original list.

For example,
Given 1->2->3->3->4->4->5, return 1->2->5.
Given 1->1->1->2->3, return 2->3.

此题要求删除链表中所有重复出现过的元素。代码如下：

ListNode* deleteDuplicates(ListNode* head) {ListNode tmpHead(-1);ListNode *pTail = &tmpHead;ListNode *pNode = head;while (pNode){ListNode* pNext = pNode->next;if (pNext == NULL || pNode->val!=pNext->val){pNode->next = pTail->next;pTail->next = pNode;pTail = pTail->next;pNode = pNext;}else{while (pNext && pNext->val ==pNode->val){pNext =pNext->next;}pNode = pNext;}}return tmpHead.next;}