Question

import java.io.*;
import java.util.*;

class Question implements Serializable {
    private static final long serialVersionUID = 1L;

    private String text;
    private List<String> options;
    private int correctOptionIndex;

    public Question(String text, List<String> options, int correctOptionIndex) {
        this.text = text;
        this.options = options;
        this.correctOptionIndex = correctOptionIndex;
    }

    public String getText() {
        return text;
    }

    public List<String> getOptions() {
        return options;
    }

    public int getCorrectOptionIndex() {
        return correctOptionIndex;
    }
}

class Quiz implements Serializable {
    private static final long serialVersionUID = 1L;

    private List<Question> questions;
    private int score;

    public Quiz() {
        questions = new ArrayList<>();
        score = 0;
        initializeQuiz();
    }

    private void initializeQuiz() {
        // Add your quiz questions here
        List<String> options1 = Arrays.asList("A. Java", "B. Python", "C. C++", "D. JavaScript");
        questions.add(new Question("Which programming language is often used for Android app development?", options1, 0));

        List<String> options2 = Arrays.asList("A. 1492", "B. 1776", "C. 1066", "D. 1215");
        questions.add(new Question("In what year did Christopher Columbus sail to America?", options2, 0));

        List<String> options3 = Arrays.asList("A. Mercury", "B. Venus", "C. Mars", "D. Jupiter");
        questions.add(new Question("Which planet is known as the 'Red Planet'?", options3, 2));
    }

    public void startQuiz() {
        Scanner scanner = new Scanner(System.in);

        for (Question question : questions) {
            displayQuestion(question);
            int userChoice = getUserChoice(scanner, question.getOptions().size());

            if (userChoice == question.getCorrectOptionIndex()) {
                System.out.println("Correct!");
                score++;
            } else {
                System.out.println("Incorrect! The correct answer is: " + question.getOptions().get(question.getCorrectOptionIndex()));
            }
        }

        System.out.println("\nQuiz complete! Your score: " + score);
    }

    private void displayQuestion(Question question) {
        System.out.println("\n" + question.getText());
        for (int i = 0; i < question.getOptions().size(); i++) {
            System.out.println(question.getOptions().get(i));
        }
    }

    private int getUserChoice(Scanner scanner, int optionsCount) {
        int userChoice = -1;
        while (userChoice < 0 || userChoice >= optionsCount) {
            System.out.println("Enter the number of your choice (0-" + (optionsCount - 1) + "): ");
            try {
                userChoice = Integer.parseInt(scanner.nextLine());
            } catch (NumberFormatException e) {
                System.out.println("Invalid input. Please enter a number.");
            }
        }
        return userChoice;
    }

    public void saveQuizResultsToFile(String filename) {
        try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(filename))) {
            oos.writeObject(this);
            System.out.println("Quiz results saved to file: " + filename);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static Quiz loadQuizResultsFromFile(String filename) {
        try (ObjectInputStream ois = new ObjectInputStream(new FileInputStream(filename))) {
            return (Quiz) ois.readObject();
        } catch (IOException | ClassNotFoundException e) {
            e.printStackTrace();
            return new Quiz(); // If an error occurs, return a new quiz instance
        }
    }
}

public class QuizGame {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.println("Welcome to the Quiz Game!");
        System.out.println("1. Start a new quiz");
        System.out.println("2. Load previous quiz results");
        System.out.println("3. Exit");

        int choice = scanner.nextInt();
        scanner.nextLine(); // Clear buffer

        switch (choice) {
            case 1:
                Quiz quiz = new Quiz();
                quiz.startQuiz();
                System.out.println("Do you want to save your quiz results? (Y/N)");
                String saveChoice = scanner.nextLine();
                if (saveChoice.equalsIgnoreCase("Y")) {
                    quiz.saveQuizResultsToFile("quiz_results.dat");
                }
                break;
            case 2:
                Quiz previousQuiz = Quiz.loadQuizResultsFromFile("quiz_results.dat");
                System.out.println("Previous quiz results loaded. Your previous score: " + previousQuiz.score);
                break;
            case 3:
                System.out.println("Goodbye!");
                System.exit(0);
                break;
            default:
                System.out.println("Invalid choice. Exiting.");
                System.exit(1);
        }
    }
}