6
int main(int argc, char **argv)
8
cout << chrono::duration<int, ratio<1>>(30).count() << endl;
9
cout << chrono::duration<int, milli>(30).count() << endl;
12
// chrono::system_clock::to_time_t
14
// chrono::system_clock::from_time_t(time(0))
16
chrono::system_clock::to_time_t
28
//chrono::duration<int, ratio<1>>(time(0))
29
chrono::minutes(time(0)/60)