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
        if(!head||!head->next)
            return head;
        ListNode *pre,*cur;
        cur=head;
        map<int,int>m;
        while(head){
            if(m[head->val]){
                pre->next=head->next;
                head=head->next;
                continue;
            }
            else {
                m[head->val]=1;
            }
            pre=head;
            head=head->next;
        }
        return cur;
    }
};