题解 | #哑结点+记录值—删除有序链表中重复的元素-II#

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */
/*哑结点方便处理头节点。temp记录重复值，方便删除*/
class Solution {
public:
    /**
     * 
     * @param head ListNode类 
     * @return ListNode类
     */
    ListNode* deleteDuplicates(ListNode* head) {
        // write code here
        ListNode *ymm = new ListNode(0);
        ymm ->next = head;
        ListNode *cur = ymm;
        while (cur->next!=nullptr && cur->next->next != nullptr) {
            if(cur->next->val == cur->next->next->val){
                int temp = cur->next->val;
                while (cur->next!=nullptr && cur->next->val == temp) {
                    cur->next = cur->next->next;
                }
            }else{
                cur = cur->next;
            }
        }
        return ymm->next;
    }
};