myfunc(10ms);
myfunc(3h);

using namespace std::chrono_literals;

void myFunc(const std::chrono::duration<double, std::ratio<1, 1>>& duration)
{
    std::cout << "duration is: " << duration.count() << std::endl;
}

int main(int argc, const char * argv[])
{
    myFunc(1ms);
    myFunc(1s);
    myFunc(1min);
    myFunc(1h);

    system("pause");
}

duration is: 0.001
duration is: 1
duration is: 60
duration is: 3600