leetcode

0 class AuthenticationManager {

1 const int ttl;

2 mutable unordered_map<string, int> expire;

3

4 public:

5 AuthenticationManager(int timeToLive) : ttl(timeToLive) {}

6

7 void generate(const string &tokenId, int currentTime) const {

8 expire.emplace(tokenId, currentTime + ttl);

9 }

10

11 void renew(const string &tokenId, int currentTime) const {

12 auto it = expire.find(tokenId);

13 if (it == end(expire)) return;

14 if (it->second <= currentTime) {

15 expire.erase(it);

16 return;

17 }

18 it->second = currentTime + ttl;

19 }

20

21 int countUnexpiredTokens(int currentTime) const {

22 for (auto it = begin(expire); it != end(expire);) {

23 if (it->second <= currentTime)

24 it = expire.erase(it);

25 else

26 it++;

27 }

28 return size(expire);

29 }

30 };