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Posted on Sep 08, 2024

the following code include //TODO implement a prediction method , you have to implement a implementation of prediction method using user-based collaborative filtering #include #include

the following code include //TODO implement a prediction method , you have to implement a implementation of prediction method using user-based collaborative filtering #include  #include  #include  #include  #include  #include  #include  #include int main() { // Open the CSV file std::ifstream file("train.csv"); if (!file.is_open()) { std::cerr << "Error: Could not open file" << std::endl; return 1; } // Maps to store the ratings for each user and movie std::unordered_map user_ratings; std::unordered_map movie_ratings; // Read the CSV file line by line file.ignore(std::numeric_limits::max(), ' '); std::string line; while (std::getline(file, line)) { // Split the line on the ',' character std::stringstream line_stream(line); std::string cell; std::vector cells; while (std::getline(line_stream, cell, ',')) { cells.push_back(cell); } // Check that we have the correct number of cells if (cells.size() != 3) { std::cerr << "Error: Invalid number of cells in line: " << line << std::endl; return 1; } // Extract the user ID, movie ID, and rating from the cells int user_id = std::stoi(cells[0]); int movie_id = std::stoi(cells[1]); int rating = std::stoi(cells[2]); // Increment the rating count for the user and movie user_ratings[user_id]++; movie_ratings[movie_id]++; } // Sort the users and movies by rating count std::vector> user_ratings_sorted(user_ratings.begin(), user_ratings.end()); std::sort(user_ratings_sorted.begin(), user_ratings_sorted.end(), [](const auto &a, const auto &b) { return a.second > b.second; }); std::vector> movie_ratings_sorted(movie_ratings.begin(), movie_ratings.end()); std::sort(movie_ratings_sorted.begin(), movie_ratings_sorted.end(), [](const auto &a, const auto &b) { return a.second > b.second; }); // Output the top 10 users with the most ratings std::cout << "Top 10 Users with Most Ratings:" << std::endl; for (int i = 0; i < 10 && i < user_ratings_sorted.size(); i++) { std::cout << "User ID: " << user_ratings_sorted[i].first << ", Ratings: " << user_ratings_sorted[i].second << std::endl; } // Output the top 10 movies with the most ratings std::cout << std::endl << "Top 10 Movies with Most Ratings:" << std::endl; for (int i = 0; i < 10 && i < movie_ratings_sorted.size(); i++) { std::cout << "Movie ID: " << movie_ratings_sorted[i].first << ", Ratings: " << movie_ratings_sorted[i].second << std::endl; } file.close(); // Open the input and output files std::ifstream input_file("train.csv"); std::ofstream output_file("predictions.csv"); if (!input_file.is_open()) { std::cerr << "Error: Could not open input file" << std::endl; return 1; } if (!output_file.is_open()) { std::cerr << "Error: Could not open output file" << std::endl; return 1; } // Maps to store the ratings for each user and movie std::unordered_map> user_ratings1; std::unordered_map> movie_ratings1; // Read the input file line by line input_file.ignore(std::numeric_limits::max(), ' '); std::string line1; while (std::getline(input_file, line)) { // Split the line on the ',' character std::stringstream line_stream(line); std::string cell; std::vector cells; while (std::getline(line_stream, cell, ',')) { cells.push_back(cell); } // Check that we have the correct number of cells if (cells.size() != 3) { std::cerr << "Error: Invalid number of cells in line: " << line << std::endl; return 1; } // Extract the user ID, movie ID, and rating from the cells int user_id = std::stoi(cells[0]); int movie_id = std::stoi(cells[1]); int rating = std::stoi(cells[2]); // Store the rating for the user and movie user_ratings1[user_id].push_back(rating); movie_ratings1[movie_id].push_back(rating); } // Write the output file headers output_file << "id,predicted" << std::endl; // Iterate through the input file again to make predictions for each line input_file.clear(); input_file.seekg(0, std::ios::beg); input_file.ignore(std::numeric_limits::max(), ' '); while (std::getline(input_file, line)) { // Split the line on the ',' character std::stringstream line_stream(line); std::string cell; std::vector cells; while (std::getline(line_stream, cell, ',')) { cells.push_back(cell); } // Check that we have the correct number of cells if (cells.size() != 3) { std::cerr << "Error: Invalid number of cells in line: " << line << std::endl; return 1; } // Extract the user ID and movie ID from the cells int user_id = std::stoi(cells[0]); int movie_id = std::stoi(cells[1]); // Use the user and movie ratings to make a prediction int prediction = 0;  // TODO: Implement your prediction method here  // Output the "id" and "predicted" values to the output file output_file << user_id << "_" << movie_id << "," << prediction << std::endl; } // Close the input and output files input_file.close(); output_file.close(); return 0; }