题解 | 删除有序链表中重复的元素-I

/**
 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 *	ListNode(int x) : val(x), next(nullptr) {}
 * };
 */
class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param head ListNode类 
     * @return ListNode类
     */
    ListNode* deleteDuplicates(ListNode* head) {
        set<int> s;
        while(head != nullptr)  
        {
            s.insert(head -> val);
            head = head -> next;
        }

        ListNode* phead = new ListNode(-1);
        ListNode* cur = phead;
        for(int item : s) 
        {
            ListNode* p = new ListNode(item);
            cur -> next = p;
            cur = cur -> next;
        }
        return phead -> next;
    }
};