题解 | #删除有序链表中重复的元素-I#

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */

class Solution {
public:
    /**
     * 
     * @param head ListNode类 
     * @return ListNode类
     */
    ListNode* deleteDuplicates(ListNode* head) {
        // write code here
        ListNode* p1 = head;
        ListNode* p2 = head;
        if(NULL == p1 || NULL == p1->next)    return head;
        p1 = p1->next;
        while(NULL != p1)
        {
            if(p1->val == p2->val)
            {
                ListNode* temp = p1;
                p1 = p1->next;
                p2->next = p1;
                free(temp);
            }
            else
            {
                p2 = p1;
                p1 = p1->next;
            }
        }
        return head;
    }
};