);     for (int k = 0; k < num_parts; ++k)     {         int start = parts[k].first;         int end = parts[k].second;         unsigned pos = 0 + 00 + 0 + 0 * total_num_parts + start * 00;         record.set_pos(pos);          mapnik::geometry::line_string<double> line;         line.reserve(end - start);         for (int j = start; j < end; ++j)         {             double x = record.read_double();             double y = record.read_double();             line.emplace_back(x, y);         }         multi_line.push_back(std::move(line));     