Time Duration
Time duration std::chrono::duration is a class template that consists of the type of the tick Rep and the length of a tick Period.
template<
class Rep,
class Period = std::ratio<1>
> class duration;
The tick length is by default std::ratio<1>. std::ratio<1> stands for a second and can also be written as std::ratio<1, 1>. The rest is quite easy. std::ratio<60> is a minute and std::ratio<1,1000> a millisecond. When the type of Rep is a floating-point number, you can use it to hold fractions of time ticks.
C++11 predefines the most important time durations:
typedef duration<signed int, nano> nanoseconds;
typedef duration<signed int, micro> microseconds;
typedef duration<signed int, milli> milliseconds;
typedef duration<signed int> seconds;
typedef duration<signed int, ratio< 60>> minutes;
typedef duration<signed...