ForEach_v1

template <typename ForwardRange, typename Function>
void ForEach(ForwardRange& range, Function function) {
    size_t count_tread = thread::hardware_concurrency();
    size_t number_of_tasks = static_cast<size_t>(ceil(range.size() / count_tread));
    // количество элементов для одного потока
    size_t blocks_for_threads = number_of_tasks == 0 ? number_of_tasks + 1 : number_of_tasks;
    //cout << "blocks_for_threads = " << blocks_for_threads << endl;

    vector<ForwardRange::iterator> end_points;
    end_points.reserve(count_tread);
    size_t count = 1;
    for (auto it = range.begin(); it != range.end(); ++it) {
        if (count % blocks_for_threads == 0) {
            end_points.push_back(it);
            //cout << *it << endl;
        }
        ++count;
    }

    auto begin_point = range.begin();
    for (auto end_point = end_points.begin(); end_point != end_points.end(); ++end_point) {
        future<void> work_thread = async([begin_point, end_point, &function] {
            for_each(execution::seq, begin_point, *end_point, function);
        });
        //cout << **end_point << endl;
        begin_point = *end_point;
    }
    for_each(execution::par, begin_point, range.end(), function);

    //for_each(execution::par, range.begin(), range.end(), function);
}