When are my eight hours up?!

when_are_my_eight_hours_up.cpp

#include <chrono>
#include <iostream>
#include <sstream>
#include <tuple>

using namespace std::chrono_literals;

auto const get_minutes(std::string const& string)
{
    std::stringstream stream{ string };

    int tmp = 0;
    stream >> tmp;
    std::chrono::hours const hours{ tmp };

    stream.get(); // swallow the colon

    tmp = 0;
    stream >> tmp;
    std::chrono::minutes const minutes{ tmp };

    return hours + minutes;
}

constexpr auto get_hours_and_minutes(std::chrono::minutes const duration)
{
    auto const hours   = std::chrono::duration_cast<std::chrono::hours>(duration);
    auto const minutes = duration % 1h;

    return std::make_tuple(hours, minutes);
}

int main(int argc, char* argv[])
{
    std::cout << "When did you start working? (08:45): ";
	std::string start_time; std::cin >> start_time;

    std::cout << "How long were your breaks in total? (minutes): ";
    int tmp = 0; std::cin >> tmp;
    auto const breaks = std::chrono::minutes{ tmp };

    auto const end = get_minutes(start_time) + breaks + 8h;

    auto [hours, minutes] = get_hours_and_minutes(end);

	std::cout << "Your eight hours are up at " << hours.count() << ":" << minutes.count() << std::endl;
    return 0;
}