leetcode

0 class Solution {

1 public:

2 string frequencySort(string &s) const {

3 unordered_map<char, int> freq;

4 vector<string> bucket(size(s) + 1);

5

6 for (char c : s)

7 freq[c]++;

8 for (auto [c, n] : freq)

9 bucket[n].append(n, c);

10

11 string res;

12 for (int i = s.size(); i > 0; i--) {

13 if (!bucket[i].empty()) res.append(bucket[i]);

14 }

15

16 return res;

17 }

18 };

19

20 class Solution {

21 public:

22 string frequencySort(const string &s) const {

23 static pair<int, char> count[128];

24

25 for (int i = 0; i < size(count); i++)

26 count[i] = {0, i};

27 for (const char c : s)

28 count[c].first++;

29 sort(rbegin(count), rend(count));

30

31 string res;

32 for (const auto [n, c] : count)

33 res += string(n, c);

34

35 return res;

36 }

37 };