题解 | #牛群排列去重#

/**
 * 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) 
    {
        // write code here
        set<int> data;
        while(head != NULL)
        {
            data.insert(head->val);
            head = head->next;
        }
        ListNode* prev = new ListNode(0);
        ListNode* result = prev;
        for(auto it = data.begin();it != data.end();++it)
        {
            ListNode* cur = new ListNode(*it);
            prev->next = cur;
            prev = cur;
        }
        return result->next;
    }
};