std::list<T> parallel_quick_sort(std::list<T> input) { //std::cout << "parallel_quick_sort list size = " << input.size() << std::endl; thread_counter++; if(input.empty()) { return input; } std::list<T> result; result.splice(result.begin(),input,input.begin()); T const& pivot=*result.begin(); auto divide_point=std::partition(input.begin(),input.end(), [&](T const& t){return t<pivot;}); std::list<T> lower_part; lower_part.splice(lower_part.end(),input,input.begin(), divide_point); if (lower_part.size() <= 10000) { auto new_lower( sequential_quick_sort(std::move(lower_part))); if (input.size() > 1) { auto new_higher( parallel_quick_sort(std::move(input))); result.splice(result.end(),new_higher); } else { result.splice(result.end(), input); } result.splice(result.begin(),new_lower); } else { std::future<std::list<T> > new_lower( std::async(¶llel_quick_sort<T>,std::move(lower_part))); if (input.size() > 1) { auto new_higher( parallel_quick_sort(std::move(input))); result.splice(result.end(),new_higher); } else { result.splice(result.end(), input); } result.splice(result.begin(),new_lower.get()); } return result; }
std::list<T> parallel_quick_sort(std::list<T> input) { if (input.empty()) return input; std::list<T> result; result.splice(result.begin(), input, input.begin()); const T& pivot = *result.begin(); auto pt = std::partition(input.begin(), input.end(), [&](const T& x) { return x < pivot; }); std::list<T> lower_part; lower_part.splice(lower_part.end(), input, input.begin(), pt); std::future<std::list<T>> new_lower( std::async(¶llel_quick_sort<T>, std::move(lower_part))); auto new_higher = parallel_quick_sort(std::move(input)); result.splice(result.end(), new_higher); result.splice(result.begin(), new_lower.get()); return result; }
std::list<T> parallel_quick_sort(std::list<T> input) { if(input.empty()) { return input; } std::list<T> result; result.splice(result.begin(),input,input.begin()); T const& pivot=*result.begin(); auto divide_point=std::partition(input.begin(),input.end(), [&](T const& t){return t<pivot;}); std::list<T> lower_part; lower_part.splice(lower_part.end(),input,input.begin(), divide_point); std::future<std::list<T> > new_lower( std::async(¶llel_quick_sort<T>,std::move(lower_part))); auto new_higher( parallel_quick_sort(std::move(input))); result.splice(result.end(),new_higher); result.splice(result.begin(),new_lower.get()); return result; }