leetcode

0 struct elem {

1 static void reset() { id_cnt = 0; }

2 static int id_cnt;

3 int id = id_cnt++, count = 0;

4 void operator++(int) { count++; }

5 friend bool operator<(const elem &e1, const elem &e2) { return e1.count > e2.count; }

6 friend ostream &operator<<(ostream &os, const elem &e) { return os << e.id << ": " << e.count; }

7 };

8 int elem::id_cnt = 0;

9

10 class Solution {

11 const int size = 20002;

12 const int mod = 10000;

13

14 public:

15 vector<int> topKFrequent(vector<int> &nums, int k) {

16 elem::reset();

17 vector<elem> um(size);

18 for (int n : nums)

19 um[n + mod]++;

20 sort(um.begin(), um.end());

21 vector<int> res;

22 for (int i = 0; i < k; i++)

23 res.push_back(um[i].id - mod);

24 return res;

25 }

26 };