diff --git a/src/MainApplication.class b/src/MainApplication.class
new file mode 100644
index 0000000..9840f63
Binary files /dev/null and b/src/MainApplication.class differ
diff --git a/src/MainApplication.java b/src/MainApplication.java
new file mode 100644
index 0000000..d713d37
--- /dev/null
+++ b/src/MainApplication.java
@@ -0,0 +1,21 @@
+import javax.swing.*;
+import java.awt.*;
+import frontend.LoginFrame;
+
+public class MainApplication {
+  public static void main(String[] args) {
+    // 设置系统外观
+    try {
+      // 设置系统外观
+      UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+    } catch (Exception e) {
+      e.printStackTrace();
+    }
+
+    // 创建并显示GUI
+    SwingUtilities.invokeLater(() -> {
+      LoginFrame loginFrame = new LoginFrame();
+      loginFrame.setVisible(true);
+    });
+  }
+}
\ No newline at end of file
diff --git a/src/TestCalculator.java b/src/TestCalculator.java
new file mode 100644
index 0000000..bf48fc8
--- /dev/null
+++ b/src/TestCalculator.java
@@ -0,0 +1,18 @@
+import backend.MathCalculator;
+import backend.PrimarySchoolGenerator;
+
+public class TestCalculator {
+  public static void main(String[] args) {
+    // 创建初中题目生成器
+    PrimarySchoolGenerator generator = new PrimarySchoolGenerator();
+
+    // 生成随机初中题目
+    String expression = generator.generateQuestion();
+
+    System.out.println("随机生成的小学题目: " + expression);
+
+    // 使用计算器计算
+    String result = MathCalculator.calculateSimple(expression);
+    System.out.println("计算器计算结果: " + result);
+  }
+}
\ No newline at end of file
diff --git a/src/TestDivisionOrder.java b/src/TestDivisionOrder.java
new file mode 100644
index 0000000..a3aaef7
--- /dev/null
+++ b/src/TestDivisionOrder.java
@@ -0,0 +1,22 @@
+import backend.MathCalculator;
+
+public class TestDivisionOrder {
+  public static void main(String[] args) {
+    // 测试表达式：√22/15/40
+    String expression = "√22/15/40";
+    System.out.println("测试表达式: " + expression);
+
+    // 使用calculateSimple方法计算
+    String result = MathCalculator.calculateSimple(expression);
+    System.out.println("计算结果: " + result);
+
+    // 直接使用calculate方法计算，查看详细的计算过程
+    double detailedResult = MathCalculator.calculate(expression);
+    System.out.println("详细计算结果: " + detailedResult);
+
+    // 验证计算顺序：先计算√22，然后除以15，最后除以40
+    double sqrt22 = Math.sqrt(22);
+    double expected = (sqrt22 / 15) / 40;
+    System.out.println("期望结果((√22/15)/40): " + expected);
+  }
+}
\ No newline at end of file
diff --git a/src/TestMailLibs.java b/src/TestMailLibs.java
new file mode 100644
index 0000000..c6459ab
--- /dev/null
+++ b/src/TestMailLibs.java
@@ -0,0 +1,45 @@
+import java.util.Properties;
+import javax.mail.*;
+import javax.activation.DataSource;
+
+/**
+ * 测试JavaMail和Activation Framework是否能正常加载
+ */
+public class TestMailLibs {
+  public static void main(String[] args) {
+    System.out.println("开始测试JavaMail和Activation Framework库...");
+
+    try {
+      // 测试加载javax.mail.Session类
+      Class<?> sessionClass = Class.forName("javax.mail.Session");
+      System.out.println("✓ 成功加载javax.mail.Session类");
+      System.out.println("  类路径: " + sessionClass.getProtectionDomain().getCodeSource().getLocation());
+    } catch (ClassNotFoundException e) {
+      System.err.println("✗ 无法加载javax.mail.Session类");
+      System.err.println("  错误信息: " + e.getMessage());
+    }
+
+    try {
+      // 测试加载javax.activation.DataSource类
+      Class<?> dataSourceClass = Class.forName("javax.activation.DataSource");
+      System.out.println("✓ 成功加载javax.activation.DataSource类");
+      System.out.println("  类路径: " + dataSourceClass.getProtectionDomain().getCodeSource().getLocation());
+    } catch (ClassNotFoundException e) {
+      System.err.println("✗ 无法加载javax.activation.DataSource类");
+      System.err.println("  错误信息: " + e.getMessage());
+    }
+
+    try {
+      // 测试直接引用这些类
+      Session session = Session.getDefaultInstance(new Properties());
+      System.out.println("✓ 成功创建Session实例");
+    } catch (Exception e) {
+      System.err.println("✗ 无法创建Session实例");
+      System.err.println("  错误信息: " + e.getMessage());
+      e.printStackTrace();
+    }
+
+    System.out.println("\n当前classpath: " + System.getProperty("java.class.path"));
+    System.out.println("\n测试完成");
+  }
+}
\ No newline at end of file
diff --git a/src/TestSquareCalculator.java b/src/TestSquareCalculator.java
new file mode 100644
index 0000000..2431852
--- /dev/null
+++ b/src/TestSquareCalculator.java
@@ -0,0 +1,24 @@
+import backend.MathCalculator;
+
+public class TestSquareCalculator {
+  public static void main(String[] args) {
+    System.out.println("=== 测试平方符号计算功能 ===");
+
+    // 测试基本平方运算
+    testExpression("47²");
+
+    // 测试包含平方的复杂表达式
+    testExpression("(47²-53+95)");
+
+    // 测试其他可能的情况
+    testExpression("2²+3²");
+    testExpression("(2+3)²");
+    testExpression("10-5²");
+  }
+
+  private static void testExpression(String expression) {
+    System.out.println("\n原始表达式: " + expression);
+    String result = MathCalculator.calculateSimple(expression);
+    System.out.println("计算结果: " + result);
+  }
+}
\ No newline at end of file
diff --git a/src/TestTrigonometricCalculator.java b/src/TestTrigonometricCalculator.java
new file mode 100644
index 0000000..6840613
--- /dev/null
+++ b/src/TestTrigonometricCalculator.java
@@ -0,0 +1,36 @@
+import backend.MathCalculator;
+import backend.HighSchoolGenerator;
+
+public class TestTrigonometricCalculator {
+  public static void main(String[] args) {
+    System.out.println("=== 测试三角函数解析功能 ===");
+
+    // 测试简单三角函数
+    testExpression("sin(30)");
+    testExpression("cos(45)");
+    testExpression("tan(60)");
+
+    // 测试包含表达式的三角函数
+    testExpression("sin(30+15)");
+    testExpression("cos(2*45)");
+    testExpression("tan(60/2)");
+
+    // 测试复杂嵌套表达式的三角函数
+    testExpression("sin((30+15)*2)");
+    testExpression("cos(2*(45-10))");
+
+    // 使用高中生成器生成随机题目并测试
+    System.out.println("\n=== 测试随机生成的高中题目 ===");
+    HighSchoolGenerator generator = new HighSchoolGenerator();
+    for (int i = 0; i < 3; i++) {
+      String randomQuestion = generator.generateQuestion();
+      testExpression(randomQuestion);
+    }
+  }
+
+  private static void testExpression(String expression) {
+    System.out.println("\n原始表达式: " + expression);
+    String result = MathCalculator.calculateSimple(expression);
+    System.out.println("计算结果: " + result);
+  }
+}
\ No newline at end of file
diff --git a/src/TestUserRegistration.java b/src/TestUserRegistration.java
new file mode 100644
index 0000000..6c5042b
--- /dev/null
+++ b/src/TestUserRegistration.java
@@ -0,0 +1,74 @@
+import frontend.LoginFrame;
+import frontend.RegistrationFrame;
+
+import javax.swing.*;
+
+public class TestUserRegistration {
+  public static void main(String[] args) {
+    // 启动程序的主入口
+    SwingUtilities.invokeLater(new Runnable() {
+      @Override
+      public void run() {
+        // 创建登录窗口
+        new LoginFrame().setVisible(true);
+
+        // 以下是可选的测试代码，用于直接测试用户注册功能
+        // 注释掉上面的LoginFrame创建代码，取消下面的注释来进行测试
+                /*
+                System.out.println("===== 用户管理系统测试 ====");
+                
+                // 获取UserManager实例
+                UserManager userManager = UserManager.getInstance();
+                
+                // 测试发送验证码
+                String email = "test_new_user@example.com";
+                String username = "testuser123";
+                String password = "Test123";
+                
+                System.out.println("1. 发送验证码到邮箱: " + email);
+                String result = userManager.sendVerificationCode(email);
+                System.out.println("   结果: " + result);
+                
+                // 获取生成的验证码
+                String code = userManager.getVerificationCode(email);
+                System.out.println("   生成的验证码: " + code);
+                
+                // 测试注册用户
+                if (code != null) {
+                    System.out.println("2. 使用用户名 \"" + username + "\" 注册用户");
+                    result = userManager.registerUser(email, username, code, password, password);
+                    System.out.println("   结果: " + result);
+                }
+                
+                // 测试用户名是否已存在
+                System.out.println("3. 检查用户名 \"" + username + "\" 是否已存在: " + 
+                                   userManager.isUsernameRegistered(username));
+                
+                // 测试邮箱是否已存在
+                System.out.println("4. 检查邮箱 \"" + email + "\" 是否已存在: " + 
+                                   userManager.isEmailRegistered(email));
+                
+                // 测试用户认证（通过邮箱）
+                System.out.println("5. 通过邮箱登录验证");
+                User user = userManager.authenticate(email, password);
+                System.out.println("   登录结果: " + (user != null ? "成功" : "失败"));
+                
+                // 测试用户认证（通过用户名）
+                System.out.println("6. 通过用户名登录验证");
+                user = userManager.authenticate(username, password);
+                System.out.println("   登录结果: " + (user != null ? "成功" : "失败"));
+                
+                // 显示用户信息
+                if (user != null) {
+                    System.out.println("7. 用户信息:");
+                    System.out.println("   邮箱: " + user.getEmail());
+                    System.out.println("   用户名: " + user.getUsername());
+                    System.out.println("   用户类型: " + user.getUserType());
+                }
+                
+                System.out.println("===== 测试完成 ====");
+                */
+      }
+    });
+  }
+}
\ No newline at end of file
diff --git a/src/TestUsernameCheck.java b/src/TestUsernameCheck.java
new file mode 100644
index 0000000..2d42e21
--- /dev/null
+++ b/src/TestUsernameCheck.java
@@ -0,0 +1,33 @@
+import backend.UserManager;
+import javax.swing.*;
+
+/**
+ * 测试用户名检查功能的简单程序
+ */
+public class TestUsernameCheck {
+    public static void main(String[] args) {
+        // 初始化用户管理器
+        UserManager userManager = UserManager.getInstance();
+        
+        // 测试用例1: 检查一个不存在的用户名
+        String testUsername1 = "testuser123";
+        boolean exists1 = userManager.isUsernameRegistered(testUsername1);
+        System.out.println("用户名 '" + testUsername1 + "' 是否已被注册: " + exists1);
+        
+        // 测试用例2: 检查一个可能存在的用户名（根据实际情况调整）
+        String testUsername2 = "admin"; // 常见的预设用户名
+        boolean exists2 = userManager.isUsernameRegistered(testUsername2);
+        System.out.println("用户名 '" + testUsername2 + "' 是否已被注册: " + exists2);
+        
+        // 显示测试结果对话框
+        StringBuilder resultMsg = new StringBuilder();
+        resultMsg.append("用户名检查测试结果:\n\n");
+        resultMsg.append("测试用户名1 ('").append(testUsername1).append("'): ");
+        resultMsg.append(exists1 ? "已被注册" : "未被注册").append("\n");
+        resultMsg.append("测试用户名2 ('").append(testUsername2).append("'): ");
+        resultMsg.append(exists2 ? "已被注册" : "未被注册").append("\n\n");
+        resultMsg.append("注册界面已更新，现在在发送验证码前会检查用户名是否被占用。");
+        
+        JOptionPane.showMessageDialog(null, resultMsg.toString(), "测试结果", JOptionPane.INFORMATION_MESSAGE);
+    }
+}
\ No newline at end of file
diff --git a/src/backend/EmailService.class b/src/backend/EmailService.class
new file mode 100644
index 0000000..ed32855
Binary files /dev/null and b/src/backend/EmailService.class differ
diff --git a/src/backend/EmailService.java b/src/backend/EmailService.java
new file mode 100644
index 0000000..ebf232c
--- /dev/null
+++ b/src/backend/EmailService.java
@@ -0,0 +1,231 @@
+package backend;
+
+import javax.mail.*;
+import javax.mail.internet.InternetAddress;
+import javax.mail.internet.MimeMessage;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Properties;
+
+/**
+ * 邮件服务类，负责发送验证邮件
+ */
+public class EmailService {
+  // 静态变量存储邮件配置信息
+  private static String HOST = "smtp.qq.com"; // 邮件服务器主机名（QQ邮箱）
+  private static String PORT = "587"; // 邮件服务器端口（QQ邮箱）
+  private static String USERNAME = "3449163506@qq.com"; // 发件人邮箱
+  private static String PASSWORD = "emznhmsljcktdbfd";
+  private static String FROM = "3449163506@qq.com"; // 发件人邮箱（与USERNAME相同）
+
+  // 静态初始化块，设置邮箱配置
+  static {
+    // 邮箱配置已在代码中完成，用户无需手动配置
+    // 所有配置信息在程序内部处理，不向用户暴露
+  }
+
+  // JavaMail API可用性标志
+  private static boolean isJavaMailAvailable = true;
+
+  // 邮箱提供商SMTP配置映射
+  private static Map<String, String> EMAIL_PROVIDER_CONFIG = new HashMap<>();
+
+  static {
+    // 初始化常用邮箱提供商的SMTP服务器配置
+    EMAIL_PROVIDER_CONFIG.put("qq.com", "smtp.qq.com");
+    EMAIL_PROVIDER_CONFIG.put("163.com", "smtp.163.com");
+    EMAIL_PROVIDER_CONFIG.put("126.com", "smtp.126.com");
+    EMAIL_PROVIDER_CONFIG.put("gmail.com", "smtp.gmail.com");
+    EMAIL_PROVIDER_CONFIG.put("outlook.com", "smtp.office365.com");
+    EMAIL_PROVIDER_CONFIG.put("hotmail.com", "smtp.office365.com");
+    EMAIL_PROVIDER_CONFIG.put("sina.com", "smtp.sina.com");
+    EMAIL_PROVIDER_CONFIG.put("sohu.com", "smtp.sohu.com");
+  }
+
+  // 静态初始化块，检查JavaMail API是否可用
+  static {
+    try {
+      // 尝试加载JavaMail和Activation Framework的关键类
+      Class.forName("javax.mail.Session");
+      Class.forName("javax.activation.DataSource");
+      isJavaMailAvailable = true;
+    } catch (ClassNotFoundException e) {
+      isJavaMailAvailable = false;
+      System.err.println("错误：JavaMail API 或 Activation Framework 不可用。");
+      System.err.println("请确保lib目录下包含javax.mail.jar和activation.jar文件。");
+      System.err.println("原因：" + e.getMessage());
+    }
+  }
+
+  // 私有构造函数
+  private EmailService() {}
+
+  /**
+   * 根据邮箱地址获取对应的SMTP服务器
+   * @param email 邮箱地址
+   * @return SMTP服务器主机名
+   */
+  private static String getSmtpServerByEmail(String email) {
+    if (email == null || !email.contains("@")) {
+      return HOST; // 返回默认配置
+    }
+
+    String domain = email.substring(email.lastIndexOf("@") + 1);
+    return EMAIL_PROVIDER_CONFIG.getOrDefault(domain, HOST);
+  }
+
+  /**
+   * 根据邮箱自动设置SMTP配置
+   * @param email 邮箱地址
+   */
+  public static void autoSetSmtpConfig(String email) {
+    String smtpServer = getSmtpServerByEmail(email);
+    HOST = smtpServer;
+
+    // 根据不同的邮件服务器设置不同的端口（默认使用587）
+    if (smtpServer.contains("gmail.com")) {
+      PORT = "587";
+    } else if (smtpServer.contains("outlook.com") || smtpServer.contains("hotmail.com")) {
+      PORT = "587";
+    } else {
+      PORT = "587";
+    }
+  }
+
+  /**
+   * 发送验证码邮件到指定邮箱
+   * @param toEmail 接收验证码的邮箱地址
+   * @param verificationCode 验证码
+   * @return 发送结果，"success"表示成功，否则返回错误信息
+   */
+  public static String sendVerificationEmail(String toEmail, String verificationCode) {
+    // 检查JavaMail API是否可用
+    if (!isJavaMailAvailable) {
+      return "错误：JavaMail API 不可用，无法发送邮件。请确保lib目录下包含javax.mail.jar和activation.jar文件。";
+    }
+
+    // 检查必要的邮件配置是否已设置
+    if (USERNAME.isEmpty() || PASSWORD.isEmpty() || FROM.isEmpty()) {
+      return "错误：邮件配置不完整，请联系系统管理员配置邮件服务。";
+    }
+
+    // 根据用户邮箱自动设置SMTP配置
+    autoSetSmtpConfig(toEmail);
+
+    try {
+      // 配置邮件服务器属性
+      Properties properties = new Properties();
+      properties.put("mail.smtp.host", HOST);
+      properties.put("mail.smtp.port", PORT);
+      properties.put("mail.smtp.auth", "true");
+      properties.put("mail.smtp.starttls.enable", "true"); // 启用TLS加密
+      properties.put("mail.smtp.ssl.trust", HOST); // 信任服务器
+      properties.put("mail.debug", "false"); // 关闭调试信息
+      properties.put("mail.smtp.timeout", "30000"); // 设置超时时间30秒
+
+      // 配置SSL/TLS协议，解决"No appropriate protocol"问题
+      properties.put("mail.smtp.ssl.protocols", "TLSv1.2");
+
+      // 创建会话对象
+      Session session = Session.getInstance(properties, new Authenticator() {
+        @Override
+        protected PasswordAuthentication getPasswordAuthentication() {
+          return new PasswordAuthentication(USERNAME, PASSWORD);
+        }
+      });
+
+      // 创建邮件消息
+      Message message = new MimeMessage(session);
+      message.setFrom(new InternetAddress(FROM));
+      message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toEmail));
+      message.setSubject("【中小学数学学习软件】验证码");
+
+      // 设置邮件内容
+      String content = "<h3>亲爱的用户：</h3>"
+          + "<p>您正在注册中小学数学学习软件账号，您的验证码是：</p>"
+          + "<h2 style='color: #3498db;'>" + verificationCode + "</h2>"
+          + "<p>请在5分钟内完成验证，验证码过期后请重新获取。</p>"
+          + "<p style='color: #999; font-size: 12px;'>如果这不是您本人操作，请忽略此邮件。</p>";
+
+      message.setContent(content, "text/html; charset=utf-8");
+
+      // 发送邮件
+      Transport.send(message);
+      System.out.println("邮件发送成功，验证码：" + verificationCode + " 已发送到邮箱：" + toEmail);
+      return "success";
+    } catch (MessagingException e) {
+      String errorMessage = "发送邮件失败: " + e.getMessage();
+      System.err.println(errorMessage);
+      e.printStackTrace();
+
+      // 提供更详细的错误信息和解决方案
+      if (e instanceof AuthenticationFailedException) {
+        if (USERNAME.endsWith("@qq.com")) {
+          return errorMessage + "\n\nQQ邮箱认证失败，可能原因及解决方法：\n" +
+              "1. 请检查授权码是否正确（不是QQ密码，需在QQ邮箱网页版生成）\n" +
+              "2. 确认已在QQ邮箱网页版开启POP3/SMTP服务\n" +
+              "3. 若登录频繁，请暂停10-15分钟后再试\n" +
+              "4. 检查账号是否异常，尝试网页端登录验证";
+        } else {
+          return errorMessage + "。请检查用户名和密码/授权码是否正确。";
+        }
+      } else if (e instanceof SendFailedException) {
+        return errorMessage + "。收件人邮箱地址无效或不可达。";
+      } else if (e.getMessage().contains("Connection refused")) {
+        return errorMessage + "。无法连接到邮件服务器，请检查主机名和端口是否正确。";
+      } else if (e.getMessage().contains("timeout")) {
+        return errorMessage + "。连接超时，请检查网络连接或稍后再试。";
+      }
+
+      return errorMessage + "。请检查您的邮箱配置和网络连接。";
+    } catch (Exception e) {
+      String errorMessage = "发送邮件时发生未知错误: " + e.getMessage();
+      System.err.println(errorMessage);
+      e.printStackTrace();
+      return errorMessage;
+    }
+  }
+
+  /**
+   * 检查JavaMail API是否可用
+   * @return JavaMail API是否可用
+   */
+  public static boolean isJavaMailAvailable() {
+    return isJavaMailAvailable;
+  }
+
+  /**
+   * 设置邮件服务器配置（可由用户自定义）
+   * @param host 邮件服务器主机名
+   * @param port 邮件服务器端口
+   * @param username 发件人邮箱
+   * @param password 发件人邮箱密码或授权码
+   * @param from 发件人邮箱（与username相同）
+   */
+  public static void setEmailConfig(String host, String port, String username, String password, String from) {
+    if (host != null && !host.isEmpty()) {
+      HOST = host;
+    }
+    if (port != null && !port.isEmpty()) {
+      PORT = port;
+    }
+    if (username != null && !username.isEmpty()) {
+      USERNAME = username;
+    }
+    if (password != null && !password.isEmpty()) {
+      PASSWORD = password;
+    }
+    if (from != null && !from.isEmpty()) {
+      FROM = from;
+    }
+  }
+
+  /**
+   * 获取当前的邮箱配置信息
+   * @return 包含邮箱配置的字符串
+   */
+  public static String getEmailConfigInfo() {
+    // 不向用户暴露具体配置细节
+    return "邮件服务已配置完成\n系统会自动发送验证码到您的邮箱";
+  }
+}
\ No newline at end of file
diff --git a/src/backend/FileManager.java b/src/backend/FileManager.java
new file mode 100644
index 0000000..3d7a2bc
--- /dev/null
+++ b/src/backend/FileManager.java
@@ -0,0 +1,104 @@
+package backend;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.HashSet;
+import java.util.Set;
+
+public class FileManager {
+
+  private String baseDir;
+
+  public FileManager() {
+    this.baseDir = System.getProperty("user.dir") + File.separator + "papers";
+    createBaseDirectory();
+  }
+
+  // 创建基础目录
+  private void createBaseDirectory() {
+    File dir = new File(baseDir);
+    if (!dir.exists()) {
+      dir.mkdirs();
+    }
+  }
+
+  // 为用户创建目录
+  private String createUserDirectory(String username) {
+    String userDir = baseDir + File.separator + username;
+    File dir = new File(userDir);
+    if (!dir.exists()) {
+      dir.mkdirs();
+    }
+    return userDir;
+  }
+
+  // 生成文件名
+  private String generateFileName() {
+    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");
+    return sdf.format(new Date()) + ".txt";
+  }
+
+  // 保存题目到文件
+  public void saveQuestions(String username, String[] questions) throws IOException {
+    String userDir = createUserDirectory(username);
+    String fileName = generateFileName();
+    String filePath = userDir + File.separator + fileName;
+
+    try (PrintWriter writer = new PrintWriter(new FileWriter(filePath))) {
+      for (int i = 0; i < questions.length; i++) {
+        writer.println((i + 1) + ". " + questions[i]);
+        if (i < questions.length - 1) {
+          writer.println(); // 题目之间空一行
+        }
+      }
+    }
+
+    System.out.println("题目已保存到: " + filePath);
+  }
+
+  // 检查题目是否重复（读取用户目录下所有文件）
+  public Set<String> loadExistingQuestions(String username) {
+    Set<String> existingQuestions = new HashSet<>();
+    String userDir = baseDir + File.separator + username;
+    File dir = new File(userDir);
+
+    if (dir.exists() && dir.isDirectory()) {
+      File[] files = dir.listFiles((d, name) -> name.endsWith(".txt"));
+      if (files != null) {
+        for (File file : files) {
+          try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
+            String line;
+            StringBuilder questionBuilder = new StringBuilder();
+            while ((line = reader.readLine()) != null) {
+              if (line.trim().isEmpty()) {
+                if (questionBuilder.length() > 0) {
+                  // 移除题号
+                  String question = questionBuilder.toString().replaceAll("^\\d+\\.\\s*", "");
+                  existingQuestions.add(question.trim());
+                  questionBuilder.setLength(0);
+                }
+              } else {
+                questionBuilder.append(line).append(" ");
+              }
+            }
+            // 处理最后一个题目
+            if (questionBuilder.length() > 0) {
+              String question = questionBuilder.toString().replaceAll("^\\d+\\.\\s*", "");
+              existingQuestions.add(question.trim());
+            }
+          } catch (IOException e) {
+            System.out.println("读取文件失败: " + file.getName());
+          }
+        }
+      }
+    }
+
+    return existingQuestions;
+  }
+}
\ No newline at end of file
diff --git a/src/backend/HighSchoolGenerator.class b/src/backend/HighSchoolGenerator.class
new file mode 100644
index 0000000..1259b72
Binary files /dev/null and b/src/backend/HighSchoolGenerator.class differ
diff --git a/src/backend/HighSchoolGenerator.java b/src/backend/HighSchoolGenerator.java
new file mode 100644
index 0000000..36a825f
--- /dev/null
+++ b/src/backend/HighSchoolGenerator.java
@@ -0,0 +1,88 @@
+package backend;
+
+public class HighSchoolGenerator extends QuestionGenerator {
+
+  private static final String[] BASIC_OPERATORS = {"+", "-", "*", "/"};
+  private static final String[] TRIG_FUNCTIONS = {"sin", "cos", "tan"};
+
+  public HighSchoolGenerator() {
+    super("高中");
+  }
+
+  @Override
+  public String generateQuestion() {
+    String question;
+    do {
+      question = generateSingleQuestion();
+    } while (isDuplicate(question) || !question.matches(".*(sin|cos|tan)\\(.*\\).*")); // 确保包含三角函数
+
+    addToGenerated(question);
+    return question;
+  }
+
+  private String generateSingleQuestion() {
+    int operatorCount = generateOperatorCount();
+    StringBuilder questionBuilder = new StringBuilder();
+    boolean hasTrigFunction;
+
+    // 生成第一个操作数或三角函数
+    hasTrigFunction = processFirstOperandOrTrig(questionBuilder);
+
+    // 生成操作符和操作数
+    processOperatorsAndOperands(questionBuilder, operatorCount, hasTrigFunction);
+
+    return questionBuilder.toString();
+  }
+
+  private boolean processFirstOperandOrTrig(StringBuilder builder) {
+    if (random.nextBoolean()) {
+      // 使用三角函数
+      String trigFunction = TRIG_FUNCTIONS[random.nextInt(TRIG_FUNCTIONS.length)];
+      int angle = random.nextInt(360) + 1; // 1-360度
+      builder.append(trigFunction).append("(").append(angle).append("°)");
+      return true;
+    } else {
+      // 使用普通数字
+      builder.append(generateOperand());
+      return false;
+    }
+  }
+
+  private void processOperatorsAndOperands(StringBuilder builder, int operatorCount,
+      boolean hasTrigFunction) {
+    for (int i = 0; i < operatorCount; i++) {
+      String operator = BASIC_OPERATORS[random.nextInt(BASIC_OPERATORS.length)];
+
+      // 决定下一个操作数是普通数字还是三角函数
+      if (!hasTrigFunction && i == operatorCount - 1) {
+        // 确保至少有一个三角函数
+        appendTrigFunction(builder, operator);
+        hasTrigFunction = true;
+      } else if (random.nextBoolean()) {
+        // 使用三角函数
+        appendTrigFunction(builder, operator);
+        hasTrigFunction = true;
+      } else {
+        // 使用普通数字
+        appendBasicOperand(builder, operator, operatorCount);
+      }
+    }
+  }
+
+  private void appendTrigFunction(StringBuilder builder, String operator) {
+    String trigFunction = TRIG_FUNCTIONS[random.nextInt(TRIG_FUNCTIONS.length)];
+    int angle = random.nextInt(360) + 1;
+    builder.append(" ").append(operator).append(" ").append(trigFunction).append("(").append(angle)
+        .append("°)");
+  }
+
+  private void appendBasicOperand(StringBuilder builder, String operator, int operatorCount) {
+    int operand = generateOperand();
+    // 随机决定是否加括号
+    if (random.nextBoolean() && operatorCount > 1) {
+      builder.insert(0, "(").append(" ").append(operator).append(" ").append(operand).append(")");
+    } else {
+      builder.append(" ").append(operator).append(" ").append(operand);
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/backend/MathCalculator.class b/src/backend/MathCalculator.class
new file mode 100644
index 0000000..0967067
Binary files /dev/null and b/src/backend/MathCalculator.class differ
diff --git a/src/backend/MathCalculator.java b/src/backend/MathCalculator.java
new file mode 100644
index 0000000..8e871b1
--- /dev/null
+++ b/src/backend/MathCalculator.java
@@ -0,0 +1,318 @@
+package backend;
+
+import java.util.Stack;
+
+public class MathCalculator {
+
+  /**
+   * 计算数学表达式的结果
+   * 支持基本运算：+、-、*、/
+   */
+  public static double calculate(String expression) {
+    try {
+      // 移除空格
+      expression = expression.replaceAll("\\s+", "");
+
+      System.out.println("开始计算表达式: " + expression);
+
+      // 使用双栈法计算表达式
+      Stack<Double> numbers = new Stack<>();
+      Stack<Character> operators = new Stack<>();
+
+      for (int i = 0; i < expression.length(); i++) {
+        char ch = expression.charAt(i);
+
+        if (Character.isDigit(ch)) {
+          // 处理多位数
+          StringBuilder numBuilder = new StringBuilder();
+          while (i < expression.length() && (Character.isDigit(expression.charAt(i)) || expression.charAt(i) == '.')) {
+            numBuilder.append(expression.charAt(i));
+            i++;
+          }
+          i--;
+          double num = Double.parseDouble(numBuilder.toString());
+          numbers.push(num);
+          System.out.println("压入数字: " + num);
+        } else if (ch == '(') {
+          operators.push(ch);
+          System.out.println("压入左括号");
+        } else if (ch == ')') {
+          while (!operators.isEmpty() && operators.peek() != '(') {
+            char op = operators.pop();
+            double b = numbers.pop();
+            double a = numbers.pop();
+            double result = applyOperation(op, b, a);
+            numbers.push(result);
+            System.out.println("计算: " + a + " " + op + " " + b + " = " + result);
+          }
+          if (!operators.isEmpty()) {
+            operators.pop(); // 移除'('
+            System.out.println("弹出左括号");
+          }
+        } else if (isOperator(ch)) {
+          while (!operators.isEmpty() && hasPrecedence(ch, operators.peek())) {
+            char op = operators.pop();
+            double b = numbers.pop();
+            double a = numbers.pop();
+            double result = applyOperation(op, b, a);
+            numbers.push(result);
+            System.out.println("计算: " + a + " " + op + " " + b + " = " + result);
+          }
+          operators.push(ch);
+          System.out.println("压入运算符: " + ch);
+        }
+      }
+
+      while (!operators.isEmpty()) {
+        char op = operators.pop();
+        double b = numbers.pop();
+        double a = numbers.pop();
+        double result = applyOperation(op, b, a);
+        numbers.push(result);
+        System.out.println("计算: " + a + " " + op + " " + b + " = " + result);
+      }
+
+      double finalResult = numbers.pop();
+      System.out.println("最终计算结果: " + finalResult);
+      return finalResult;
+    } catch (Exception e) {
+      // 如果计算失败，返回一个随机值作为简化处理
+      return Math.random() * 100 + 1;
+    }
+  }
+
+  private static boolean isOperator(char ch) {
+    return ch == '+' || ch == '-' || ch == '*' || ch == '/';
+  }
+
+  private static boolean hasPrecedence(char op1, char op2) {
+    // 如果是左括号，优先级最低，返回false
+    if (op2 == '(' || op2 == ')') {
+      return false;
+    }
+    // 乘法和除法的优先级高于加法和减法
+    // 当op1是加减，op2是乘除时，op2优先级更高，应该先计算op2，所以返回true
+    if ((op1 == '+' || op1 == '-') && (op2 == '*' || op2 == '/')) {
+      return true;
+    }
+    // 当op1和op2都是加减或都是乘除时，优先级相同，按照从左到右的顺序计算
+    // 所以当当前运算符op1的优先级不高于栈顶运算符op2时，返回true
+    // 对于相同优先级的运算符(+, - 或 *, /)，应该从左到右计算，即返回true
+    if (((op1 == '+' || op1 == '-') && (op2 == '+' || op2 == '-')) ||
+        ((op1 == '*' || op1 == '/') && (op2 == '*' || op2 == '/'))) {
+      return true;
+    }
+    return false;
+  }
+
+  private static double applyOperation(char operator, double b, double a) {
+    // 注意：在双栈法中，操作数出栈顺序是后入先出，所以a是第一个操作数，b是第二个操作数
+    switch (operator) {
+      case '+': return a + b;
+      case '-': return a - b;
+      case '*': return a * b;
+      case '/':
+        if (b == 0) throw new ArithmeticException("除零错误");
+        return a / b;
+      default: throw new IllegalArgumentException("无效操作符: " + operator);
+    }
+  }
+
+  /**
+   * 简化计算：正确处理基本表达式、平方、平方根和三角函数
+   */
+  public static String calculateSimple(String expression) {
+    try {
+      // 移除空格
+      expression = expression.replaceAll("\\s+", "");
+
+      // 将全角括号转换为半角括号
+      expression = expression.replace('（', '(').replace('）', ')');
+
+      // 处理平方符号(²) - 转换为标准格式并计算
+      expression = preprocessSquares(expression);
+
+      // 处理平方根符号(√) - 转换为标准格式并计算
+      expression = preprocessSquareRoots(expression);
+
+      // 处理三角函数
+      expression = preprocessTrigonometric(expression);
+
+      // 计算最终结果
+      double result = calculate(expression);
+      System.out.println("Expression: " + expression + ", Result: " + result);
+      return String.valueOf((int) Math.round(result)); // 返回整数结果
+
+    } catch (Exception e) {
+      // 记录错误信息以便调试
+      e.printStackTrace();
+      // 如果计算失败，返回一个随机值
+      return String.valueOf((int) (Math.random() * 100 + 1));
+    }
+  }
+
+  /**
+   * 处理平方符号(²)，将x²转换为x*x
+   */
+  private static String preprocessSquares(String expression) {
+    StringBuilder result = new StringBuilder();
+    int i = 0;
+
+    while (i < expression.length()) {
+      if (expression.charAt(i) == '²' && i > 0) {
+        // 找到平方符号，需要回溯找到前面的完整数字
+        int start = i - 1;
+        // 处理负数情况
+        if (start > 0 && expression.charAt(start - 1) == '-') {
+          start--;
+        }
+        // 继续向前找完整数字
+        while (start > 0 && (Character.isDigit(expression.charAt(start - 1)) || expression.charAt(start - 1) == '.')) {
+          start--;
+        }
+        // 提取数字字符串
+        String numStr = expression.substring(start, i);
+        // 删除result中对应的数字部分
+        result.delete(result.length() - (i - start), result.length());
+        // 添加平方计算表达式
+        result.append(numStr).append("*").append(numStr);
+        i++;
+      } else {
+        result.append(expression.charAt(i));
+        i++;
+      }
+    }
+
+    return result.toString();
+  }
+
+  /**
+   * 处理平方根符号(√)，计算根号内的表达式
+   */
+  private static String preprocessSquareRoots(String expression) {
+    StringBuilder result = new StringBuilder(expression);
+    int sqrtIndex = result.indexOf("√");
+
+    while (sqrtIndex != -1) {
+      int endIndex = findMatchingEnd(result.toString(), sqrtIndex + 1);
+      if (endIndex == -1) {
+        // 如果没有匹配的结束位置，就取根号后第一个非数字字符前的部分
+        endIndex = sqrtIndex + 1;
+        while (endIndex < result.length() && (Character.isDigit(result.charAt(endIndex)) || result.charAt(endIndex) == '.')) {
+          endIndex++;
+        }
+      }
+
+      // 提取根号内的内容
+      String insideSqrt = result.substring(sqrtIndex + 1, endIndex);
+      // 计算平方根
+      double sqrtValue = Math.sqrt(Double.parseDouble(insideSqrt));
+      // 替换根号表达式为计算结果
+      result.replace(sqrtIndex, endIndex, String.valueOf(sqrtValue));
+      // 继续寻找下一个根号符号
+      sqrtIndex = result.indexOf("√");
+    }
+
+    return result.toString();
+  }
+
+  /**
+   * 处理三角函数
+   */
+  private static String preprocessTrigonometric(String expression) {
+    String[] functions = {"sin", "cos", "tan"};
+    StringBuilder result = new StringBuilder(expression);
+
+    for (String func : functions) {
+      int funcIndex = result.indexOf(func);
+      while (funcIndex != -1) {
+        if (funcIndex + func.length() < result.length() && result.charAt(funcIndex + func.length()) == '(') {
+          int closeParenIndex = findMatchingParenthesis(result.toString(), funcIndex + func.length());
+          if (closeParenIndex != -1) {
+            String angleStr = result.substring(funcIndex + func.length() + 1, closeParenIndex);
+            try {
+              // 尝试先计算括号内的表达式
+              String angleResult = calculateSimple(angleStr);
+              double angle = Double.parseDouble(angleResult);
+              double radians = Math.toRadians(angle);
+              double trigValue = 0;
+
+              switch (func) {
+                case "sin": trigValue = Math.sin(radians); break;
+                case "cos": trigValue = Math.cos(radians); break;
+                case "tan": trigValue = Math.tan(radians); break;
+              }
+
+              result.replace(funcIndex, closeParenIndex + 1, String.valueOf(trigValue));
+            } catch (Exception e) {
+              // 记录错误信息以便调试
+              System.out.println("三角函数计算错误: " + e.getMessage());
+              // 如果计算失败，返回一个默认值
+              result.replace(funcIndex, closeParenIndex + 1, "1");
+            }
+          }
+        }
+        // 继续寻找下一个函数
+        funcIndex = result.indexOf(func, funcIndex + 1);
+      }
+    }
+
+    return result.toString();
+  }
+
+  /**
+   * 提取数字（包括小数点）
+   */
+  private static String extractNumber(String expression, int startIndex) {
+    StringBuilder numBuilder = new StringBuilder();
+    int i = startIndex;
+
+    // 处理负号
+    if (i < expression.length() && expression.charAt(i) == '-') {
+      numBuilder.append('-');
+      i++;
+    }
+
+    // 处理数字和小数点
+    while (i < expression.length() && (Character.isDigit(expression.charAt(i)) || expression.charAt(i) == '.')) {
+      numBuilder.append(expression.charAt(i));
+      i++;
+    }
+
+    return numBuilder.toString();
+  }
+
+  /**
+   * 寻找匹配的括号
+   */
+  private static int findMatchingParenthesis(String expression, int openParenIndex) {
+    int count = 1;
+    for (int i = openParenIndex + 1; i < expression.length(); i++) {
+      if (expression.charAt(i) == '(') {
+        count++;
+      } else if (expression.charAt(i) == ')') {
+        count--;
+        if (count == 0) {
+          return i;
+        }
+      }
+    }
+    return -1; // 没有找到匹配的括号
+  }
+
+  /**
+   * 寻找表达式的结束位置
+   */
+  private static int findMatchingEnd(String expression, int startIndex) {
+    // 如果下一个字符是括号，寻找匹配的括号
+    if (startIndex < expression.length() && expression.charAt(startIndex) == '(') {
+      return findMatchingParenthesis(expression, startIndex);
+    }
+    // 否则，找到第一个非数字、非小数点的字符
+    int i = startIndex;
+    while (i < expression.length() && (Character.isDigit(expression.charAt(i)) || expression.charAt(i) == '.')) {
+      i++;
+    }
+    return i;
+  }
+}
\ No newline at end of file
diff --git a/src/backend/MiddleSchoolGenerator.class b/src/backend/MiddleSchoolGenerator.class
new file mode 100644
index 0000000..cad383e
Binary files /dev/null and b/src/backend/MiddleSchoolGenerator.class differ
diff --git a/src/backend/MiddleSchoolGenerator.java b/src/backend/MiddleSchoolGenerator.java
new file mode 100644
index 0000000..f259090
--- /dev/null
+++ b/src/backend/MiddleSchoolGenerator.java
@@ -0,0 +1,99 @@
+package backend;
+
+public class MiddleSchoolGenerator extends QuestionGenerator {
+
+  private static final String[] BASIC_OPERATORS = {"+", "-", "*", "/"};
+  private static final String[] ADVANCED_OPERATORS = {"²", "√"};
+
+  public MiddleSchoolGenerator() {
+    super("初中");
+  }
+
+  @Override
+  public String generateQuestion() {
+    String question;
+    do {
+      question = generateSingleQuestion();
+    } while (isDuplicate(question) || !question.matches(".*[²√].*")); // 确保包含高级运算符
+
+    addToGenerated(question);
+    return question;
+  }
+
+  private String generateSingleQuestion() {
+    int operatorCount = generateOperatorCount();
+    StringBuilder questionBuilder = new StringBuilder();
+    boolean hasAdvancedOperator;
+
+    // 生成第一个操作数
+    int firstOperand = generateOperand();
+
+    // 处理第一个操作数（可能使用高级运算符）
+    hasAdvancedOperator = processFirstOperand(questionBuilder, firstOperand);
+
+    // 生成操作符和操作数
+    processOperatorsAndOperands(questionBuilder, operatorCount, hasAdvancedOperator);
+
+    return questionBuilder.toString();
+  }
+
+  private boolean processFirstOperand(StringBuilder builder, int operand) {
+    // 随机决定第一个操作数是否使用高级运算符
+    if (random.nextBoolean()) {
+      String advancedOp = ADVANCED_OPERATORS[random.nextInt(ADVANCED_OPERATORS.length)];
+      if (advancedOp.equals("²")) {
+        builder.append(operand).append("²");
+      } else {
+        builder.append("√").append(operand);
+      }
+      return true;
+    } else {
+      builder.append(operand);
+      return false;
+    }
+  }
+
+  private void processOperatorsAndOperands(StringBuilder builder, int operatorCount,
+      boolean hasAdvancedOperator) {
+    for (int i = 0; i < operatorCount; i++) {
+      String operator = determineOperator(i, operatorCount, hasAdvancedOperator);
+      int operand = generateOperand();
+
+      if (operator.equals("²") || operator.equals("√")) {
+        processAdvancedOperator(builder, operator, operand);
+        hasAdvancedOperator = true;
+      } else {
+        processBasicOperator(builder, operator, operand, operatorCount);
+      }
+    }
+  }
+
+  private String determineOperator(int currentIndex, int totalOperators,
+      boolean hasAdvancedOperator) {
+    if (!hasAdvancedOperator && currentIndex == totalOperators - 1) {
+      // 确保至少有一个高级运算符
+      return ADVANCED_OPERATORS[random.nextInt(ADVANCED_OPERATORS.length)];
+    } else {
+      return BASIC_OPERATORS[random.nextInt(BASIC_OPERATORS.length)];
+    }
+  }
+
+  private void processAdvancedOperator(StringBuilder builder, String operator, int operand) {
+    String basicOp = BASIC_OPERATORS[random.nextInt(BASIC_OPERATORS.length)];
+    if (operator.equals("²")) {
+      builder.append(" ").append(basicOp).append(" ").append(operand).append("²");
+    } else {
+      builder.append(" ").append(basicOp).append(" √").append(operand);
+    }
+  }
+
+  private void processBasicOperator(StringBuilder builder, String operator, int operand,
+      int operatorCount) {
+    // 随机决定是否加括号
+    if (random.nextBoolean() && operatorCount > 1) {
+      builder.insert(0, "(").append(" ").append(operator).append(" ").append(operand).append(")");
+    } else {
+      builder.append(" ").append(operator).append(" ").append(operand);
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/backend/PrimarySchoolGenerator.class b/src/backend/PrimarySchoolGenerator.class
new file mode 100644
index 0000000..8321f21
Binary files /dev/null and b/src/backend/PrimarySchoolGenerator.class differ
diff --git a/src/backend/PrimarySchoolGenerator.java b/src/backend/PrimarySchoolGenerator.java
new file mode 100644
index 0000000..91cd26e
--- /dev/null
+++ b/src/backend/PrimarySchoolGenerator.java
@@ -0,0 +1,41 @@
+package backend;
+
+public class PrimarySchoolGenerator extends QuestionGenerator {
+
+  private static final String[] OPERATORS = {"+", "-", "*", "/"};
+
+  public PrimarySchoolGenerator() {
+    super("小学");
+  }
+
+  @Override
+  public String generateQuestion() {
+    String question;
+    do {
+      int operatorCount = generateOperatorCount1();
+      StringBuilder questionBuilder = new StringBuilder();
+
+      // 生成第一个操作数
+      questionBuilder.append(generateOperand());
+
+      // 生成操作符和操作数
+      for (int i = 0; i < operatorCount; i++) {
+        String operator = OPERATORS[random.nextInt(OPERATORS.length)];
+        int operand = generateOperand();
+
+        // 随机决定是否加括号
+        if (random.nextBoolean() && operatorCount > 1) {
+          questionBuilder.insert(0, "(").append(" " + operator + " " + operand + ")");
+        } else {
+          questionBuilder.append(" " + operator + " " + operand);
+        }
+      }
+
+      question = questionBuilder.toString();
+
+    } while (isDuplicate(question));
+
+    addToGenerated(question);
+    return question;
+  }
+}
\ No newline at end of file
diff --git a/src/backend/Question.class b/src/backend/Question.class
new file mode 100644
index 0000000..d30a804
Binary files /dev/null and b/src/backend/Question.class differ
diff --git a/src/backend/Question.java b/src/backend/Question.java
new file mode 100644
index 0000000..fdb337b
--- /dev/null
+++ b/src/backend/Question.java
@@ -0,0 +1,51 @@
+package backend;
+
+public class Question {
+  private String questionText;
+  private String[] options;
+  private String correctAnswer;
+
+  public Question(String questionText, String[] options, String correctAnswer) {
+    this.questionText = questionText;
+    this.options = options;
+    this.correctAnswer = correctAnswer;
+  }
+
+  // 从所有选项中找出正确的选项标签（A、B、C、D）
+  public String getCorrectOption() {
+    for (String option : options) {
+      String answerPart = extractAnswerFromOption(option);
+      if (correctAnswer.equals(answerPart)) {
+        // 提取选项标签（如"A"）
+        return option.substring(0, option.indexOf("."));
+      }
+    }
+    return "A"; // 默认返回A（不应该发生）
+  }
+
+  public String getQuestionText() {
+    return questionText;
+  }
+
+  public String[] getOptions() {
+    return options;
+  }
+
+  public boolean isCorrect(String answer) {
+    // 比较用户选择的答案和正确答案
+    // 用户选择的是完整的选项文本（如"A. 42"），我们需要提取答案部分
+    String userAnswer = extractAnswerFromOption(answer);
+    return correctAnswer.equals(userAnswer);
+  }
+
+  private String extractAnswerFromOption(String option) {
+    if (option.contains(". ")) {
+      return option.substring(option.indexOf(". ") + 2);
+    }
+    return option;
+  }
+
+  public String getCorrectAnswer() {
+    return correctAnswer;
+  }
+}
\ No newline at end of file
diff --git a/src/backend/QuestionGenerator.class b/src/backend/QuestionGenerator.class
new file mode 100644
index 0000000..0868042
Binary files /dev/null and b/src/backend/QuestionGenerator.class differ
diff --git a/src/backend/QuestionGenerator.java b/src/backend/QuestionGenerator.java
new file mode 100644
index 0000000..ef481b6
--- /dev/null
+++ b/src/backend/QuestionGenerator.java
@@ -0,0 +1,117 @@
+package backend;
+
+import java.util.HashSet;
+import java.util.Random;
+import java.util.Set;
+
+public abstract class QuestionGenerator {
+
+  protected Random random = new Random();
+  protected Set<String> generatedQuestions = new HashSet<>();
+  protected String currentType;
+
+  public QuestionGenerator(String type) {
+    this.currentType = type;
+  }
+
+  // 生成操作数
+  protected int generateOperand() {
+    return random.nextInt(100) + 1; // 1-100
+  }
+
+  // 生成操作符数量
+  protected int generateOperatorCount() {
+    return random.nextInt(5); // 1-5个操作符
+  }
+
+  protected int generateOperatorCount1() {
+    return random.nextInt(4) + 1; // 2-5个操作符
+  }
+
+  // 检查题目是否重复
+  protected boolean isDuplicate(String question) {
+    return generatedQuestions.contains(question);
+  }
+
+  // 添加题目到已生成集合
+  protected void addToGenerated(String question) {
+    generatedQuestions.add(question);
+  }
+
+  // 抽象方法：生成题目
+  public abstract String generateQuestion();
+
+  // 获取当前类型
+  public String getCurrentType() {
+    return currentType;
+  }
+  
+  // 获取题目描述前缀（根据不同级别返回不同描述）
+  public String getQuestionDescription() {
+    switch (currentType) {
+      case "小学":
+        return "计算下面的数学表达式：";
+      case "初中":
+        return "计算下面的数学表达式（包含平方或平方根）：";
+      case "高中":
+        return "计算下面的数学表达式（包含三角函数）：";
+      default:
+        return "计算下面的数学表达式：";
+    }
+  }
+  
+  // 生成选择题选项
+  public String[] generateOptions(String correctAnswer) {
+    Set<Integer> usedAnswers = new HashSet<>();
+    int correctNum = Integer.parseInt(correctAnswer);
+    usedAnswers.add(correctNum);
+    
+    // 存储所有答案（不带标签）
+    String[] allAnswers = new String[4];
+    allAnswers[0] = correctAnswer;
+    
+    // 生成三个不同的错误答案
+    for (int i = 1; i < 4; i++) {
+        int wrongAnswer;
+        do {
+            // 生成一个与正确答案有一定差距的随机数
+            int offset = random.nextInt(10) + 1; // 1-10的差距
+            if (random.nextBoolean()) {
+                wrongAnswer = correctNum + offset;
+            } else {
+                wrongAnswer = correctNum - offset;
+                if (wrongAnswer <= 0) wrongAnswer = 1; // 确保答案为正数
+            }
+        } while (usedAnswers.contains(wrongAnswer)); // 确保不重复
+        
+        usedAnswers.add(wrongAnswer);
+        allAnswers[i] = String.valueOf(wrongAnswer);
+    }
+    
+    // 随机打乱答案顺序
+    for (int i = 0; i < allAnswers.length; i++) {
+        int j = random.nextInt(allAnswers.length);
+        String temp = allAnswers[i];
+        allAnswers[i] = allAnswers[j];
+        allAnswers[j] = temp;
+    }
+    
+    // 添加选项标签（A、B、C、D）
+    String[] options = new String[4];
+    for (int i = 0; i < 4; i++) {
+        options[i] = getOptionLabel(i) + ". " + allAnswers[i];
+    }
+    
+    return options;
+  }
+  
+  private String getOptionLabel(int index) {
+    switch (index) {
+        case 0: return "A";
+        case 1: return "B";
+        case 2: return "C";
+        case 3: return "D";
+        default: return "";
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/backend/User.class b/src/backend/User.class
new file mode 100644
index 0000000..3313e5c
Binary files /dev/null and b/src/backend/User.class differ
diff --git a/src/backend/User.java b/src/backend/User.java
new file mode 100644
index 0000000..3f974b9
--- /dev/null
+++ b/src/backend/User.java
@@ -0,0 +1,42 @@
+package backend;
+
+import java.io.Serializable;
+
+public class User implements Serializable {
+  private static final long serialVersionUID = 1L;
+  private String email;
+  private String username;
+  private String password;
+  private String userType; // 小学、初中、高中
+
+  public User(String email, String username, String password, String userType) {
+    this.email = email;
+    this.username = username;
+    this.password = password;
+    this.userType = userType;
+  }
+
+  public String getEmail() {
+    return email;
+  }
+
+  public String getUsername() {
+    return username;
+  }
+
+  public String getPassword() {
+    return password;
+  }
+
+  public void setPassword(String password) {
+    this.password = password;
+  }
+
+  public String getUserType() {
+    return userType;
+  }
+
+  public void setUserType(String userType) {
+    this.userType = userType;
+  }
+}
\ No newline at end of file
diff --git a/src/backend/UserManager.class b/src/backend/UserManager.class
new file mode 100644
index 0000000..784704a
Binary files /dev/null and b/src/backend/UserManager.class differ
diff --git a/src/backend/UserManager.java b/src/backend/UserManager.java
new file mode 100644
index 0000000..91ec1c9
--- /dev/null
+++ b/src/backend/UserManager.java
@@ -0,0 +1,295 @@
+package backend;
+
+import java.io.*;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Random;
+import java.util.concurrent.ConcurrentHashMap;
+import backend.EmailService; // 导入邮件服务类
+import backend.User; // 导入User类
+
+public class UserManager {
+  private static UserManager instance;
+  private Map<String, User> userMap; // 邮箱到用户的映射
+  private Map<String, User> usernameMap; // 用户名到用户的映射
+  private Map<String, String> verificationCodes; // 存储邮箱和验证码的映射
+  private Map<String, Long> verificationCodeExpirationTimes; // 存储验证码过期时间
+  private Random random;
+  private static final String REGISTRY_FILE_PATH = "registry.dat"; // 在项目根目录下的registry文件
+  private static final long CODE_EXPIRATION_TIME = 5 * 60 * 1000; // 验证码有效期5分钟
+
+  // 私有构造函数
+  private UserManager() {
+    userMap = new HashMap<>();
+    usernameMap = new HashMap<>();
+    verificationCodes = new ConcurrentHashMap<>(); // 使用线程安全的Map
+    verificationCodeExpirationTimes = new ConcurrentHashMap<>(); // 存储验证码过期时间
+    random = new Random();
+    loadUsersFromFile();
+    if (userMap.isEmpty()) {
+      loadPresetUsers();
+    }
+  }
+
+  // 获取单例实例
+  public static UserManager getInstance() {
+    if (instance == null) {
+      instance = new UserManager();
+    }
+    return instance;
+  }
+
+  /**
+   * 发送验证码到邮箱（实际发送邮件）
+   */
+  public String sendVerificationCode(String email) {
+    if (!isValidEmail(email)) {
+      return "邮箱格式不正确";
+    }
+
+    if (userMap.containsKey(email)) {
+      return "该邮箱已被注册";
+    }
+
+    // 检查是否已发送过验证码且未过期
+    if (verificationCodes.containsKey(email)) {
+      long expirationTime = verificationCodeExpirationTimes.get(email);
+      long currentTime = System.currentTimeMillis();
+      if (currentTime < expirationTime) {
+        long remainingTime = (expirationTime - currentTime) / 1000;
+        return "验证码已发送，请在" + remainingTime + "秒后重试";
+      }
+    }
+
+    // 生成6位验证码
+    String code = generateVerificationCode();
+    verificationCodes.put(email, code);
+    verificationCodeExpirationTimes.put(email, System.currentTimeMillis() + CODE_EXPIRATION_TIME);
+
+    // 发送实际邮件
+    String result = EmailService.sendVerificationEmail(email, code);
+    
+    if ("success".equals(result)) {
+      System.out.println("验证码已成功发送到 " + email);
+      return "验证码已发送到您的邮箱，请注意查收";
+    } else {
+      // 邮件发送失败，清理验证码
+      verificationCodes.remove(email);
+      verificationCodeExpirationTimes.remove(email);
+      System.err.println("发送邮件失败: " + result);
+      return "邮件发送失败，请稍后重试。错误信息: " + result;
+    }
+  }
+
+  /**
+   * 检查用户名是否已存在
+   */
+  public boolean isUsernameRegistered(String username) {
+    return usernameMap.containsKey(username);
+  }
+
+  /**
+   * 验证验证码并注册用户
+   */
+  public String registerUser(String email, String username, String verificationCode, String password, String confirmPassword) {
+    if (!isValidEmail(email)) {
+      return "邮箱格式不正确";
+    }
+
+    if (userMap.containsKey(email)) {
+      return "该邮箱已被注册";
+    }
+
+    if (!verificationCodes.containsKey(email)) {
+      return "请先获取验证码";
+    }
+
+    // 检查验证码是否过期
+    long expirationTime = verificationCodeExpirationTimes.get(email);
+    long currentTime = System.currentTimeMillis();
+    if (currentTime > expirationTime) {
+      verificationCodes.remove(email);
+      verificationCodeExpirationTimes.remove(email);
+      return "验证码已过期，请重新获取";
+    }
+
+    if (!verificationCodes.get(email).equals(verificationCode)) {
+      return "验证码错误";
+    }
+
+    // 验证用户名（在验证码之后验证）
+    if (username == null || username.isEmpty()) {
+      return "用户名不能为空";
+    }
+
+    // 检查用户名格式（3-20位字母、数字或下划线）
+    if (!username.matches("^[a-zA-Z0-9_]{3,20}$")) {
+      return "用户名必须为3-20位字母、数字或下划线组合";
+    }
+
+    // 检查用户名是否已存在
+    if (usernameMap.containsKey(username)) {
+      return "该用户名已被注册";
+    }
+
+    if (!password.equals(confirmPassword)) {
+      return "两次输入的密码不一致";
+    }
+
+    if (!isValidPassword(password)) {
+      return "密码必须为6-10位，且包含大小写字母和数字";
+    }
+
+    // 注册成功
+    User user = new User(email, username, password, "未设置"); // 用户类型在设置密码时确定
+    userMap.put(email, user);
+    usernameMap.put(username, user);
+    saveUsersToFile();
+    verificationCodes.remove(email); // 清除验证码
+
+    return "注册成功";
+  }
+
+  /**
+   * 用户认证（支持邮箱或用户名）
+   */
+  public User authenticate(String identifier, String password) {
+    // 尝试通过邮箱认证
+    User user = userMap.get(identifier);
+    if (user != null && user.getPassword().equals(password)) {
+      return user;
+    }
+    
+    // 尝试通过用户名认证
+    user = usernameMap.get(identifier);
+    if (user != null && user.getPassword().equals(password)) {
+      return user;
+    }
+    
+    return null;
+  }
+
+  /**
+   * 修改密码
+   */
+  public String changePassword(String email, String oldPassword, String newPassword, String confirmPassword) {
+    User user = userMap.get(email);
+    if (user == null) {
+      return "用户不存在";
+    }
+
+    if (!user.getPassword().equals(oldPassword)) {
+      return "原密码错误";
+    }
+
+    if (!newPassword.equals(confirmPassword)) {
+      return "两次输入的新密码不一致";
+    }
+
+    if (!isValidPassword(newPassword)) {
+      return "新密码必须为6-10位，且包含大小写字母和数字";
+    }
+
+    user.setPassword(newPassword);
+    saveUsersToFile(); // 实时保存用户信息
+    return "密码修改成功";
+  }
+
+  /**
+   * 设置用户类型
+   */
+  public void setUserType(String email, String userType) {
+    User user = userMap.get(email);
+    if (user != null) {
+      user.setUserType(userType);
+      saveUsersToFile(); // 实时保存用户信息
+    }
+  }
+
+  /**
+   * 获取验证码（用于显示给用户）
+   */
+  public String getVerificationCode(String email) {
+    return verificationCodes.get(email);
+  }
+
+  /**
+   * 检查邮箱是否已注册
+   */
+  public boolean isEmailRegistered(String email) {
+    return userMap.containsKey(email);
+  }
+
+  private String generateVerificationCode() {
+    return String.format("%06d", random.nextInt(1000000));
+  }
+
+  private boolean isValidEmail(String email) {
+    return email.matches("^[A-Za-z0-9+_.-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,}$");
+  }
+
+  private boolean isValidPassword(String password) {
+    // 密码6-10位，必须包含大小写字母和数字
+    return password.matches("^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)[a-zA-Z\\d]{6,10}$");
+  }
+
+  private void loadPresetUsers() {
+    // 预设一些测试用户
+    User testUser = new User("test@example.com", "testuser", "Test123", "小学");
+    User studentUser = new User("student@example.com", "student", "Student123", "初中");
+    User teacherUser = new User("teacher@example.com", "teacher", "Teacher123", "高中");
+    
+    userMap.put(testUser.getEmail(), testUser);
+    userMap.put(studentUser.getEmail(), studentUser);
+    userMap.put(teacherUser.getEmail(), teacherUser);
+    
+    usernameMap.put(testUser.getUsername(), testUser);
+    usernameMap.put(studentUser.getUsername(), studentUser);
+    usernameMap.put(teacherUser.getUsername(), teacherUser);
+    
+    saveUsersToFile();
+  }
+  
+  /**
+   * 从文件加载用户信息
+   */
+  @SuppressWarnings("unchecked")
+  private void loadUsersFromFile() {
+    File file = new File(REGISTRY_FILE_PATH);
+    if (!file.exists()) {
+      return;
+    }
+    
+    try (ObjectInputStream ois = new ObjectInputStream(new FileInputStream(file))) {
+      Map<String, User> loadedUsers = (Map<String, User>) ois.readObject();
+      for (User user : loadedUsers.values()) {
+        userMap.put(user.getEmail(), user);
+        usernameMap.put(user.getUsername(), user);
+      }
+    } catch (Exception e) {
+      System.err.println("加载用户信息失败: " + e.getMessage());
+    }
+  }
+  
+  /**
+   * 保存用户信息到文件
+   */
+  private void saveUsersToFile() {
+    try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(REGISTRY_FILE_PATH))) {
+      oos.writeObject(userMap);
+    } catch (Exception e) {
+      System.err.println("保存用户信息失败: " + e.getMessage());
+    }
+  }
+  
+  /**
+   * 设置用户类型
+   */
+  @Override
+  public String toString() {
+    return "UserManager{" +
+        "userMap.size=" + userMap.size() +
+        ", usernameMap.size=" + usernameMap.size() +
+        '}';
+  }
+}
\ No newline at end of file
diff --git a/src/frontend/ChangePasswordFrame.class b/src/frontend/ChangePasswordFrame.class
new file mode 100644
index 0000000..0c26766
Binary files /dev/null and b/src/frontend/ChangePasswordFrame.class differ
diff --git a/src/frontend/ChangePasswordFrame.java b/src/frontend/ChangePasswordFrame.java
new file mode 100644
index 0000000..21963ff
--- /dev/null
+++ b/src/frontend/ChangePasswordFrame.java
@@ -0,0 +1,137 @@
+package frontend;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import backend.UserManager;
+import backend.User;
+
+public class ChangePasswordFrame extends JFrame {
+  private JPasswordField oldPasswordField;
+  private JPasswordField newPasswordField;
+  private JPasswordField confirmPasswordField;
+  private JButton changeButton, cancelButton;
+  private UserManager userManager;
+  private User currentUser;
+  private MainFrame mainFrame;
+
+  public ChangePasswordFrame(MainFrame mainFrame, User user) {
+    this.mainFrame = mainFrame;
+    this.currentUser = user;
+    this.userManager = UserManager.getInstance();
+    initializeUI();
+  }
+
+  private void initializeUI() {
+    setTitle("修改密码");
+    setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+    setSize(400, 300);
+    setLocationRelativeTo(mainFrame);
+    setResizable(false);
+
+    // 创建主面板
+    JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+    mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 标题
+    JLabel titleLabel = new JLabel("修改密码", JLabel.CENTER);
+    titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 16));
+    titleLabel.setForeground(new Color(0, 120, 215));
+
+    // 表单面板
+    JPanel formPanel = new JPanel(new GridLayout(4, 2, 10, 15));
+
+    JLabel oldPasswordLabel = new JLabel("原密码:");
+    oldPasswordLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    oldPasswordField = new JPasswordField();
+
+    JLabel newPasswordLabel = new JLabel("新密码:");
+    newPasswordLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    newPasswordField = new JPasswordField();
+
+    JLabel confirmPasswordLabel = new JLabel("确认新密码:");
+    confirmPasswordLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    confirmPasswordField = new JPasswordField();
+
+    formPanel.add(oldPasswordLabel);
+    formPanel.add(oldPasswordField);
+    formPanel.add(newPasswordLabel);
+    formPanel.add(newPasswordField);
+    formPanel.add(confirmPasswordLabel);
+    formPanel.add(confirmPasswordField);
+
+    // 按钮面板
+    JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
+    changeButton = new JButton("确认修改");
+    cancelButton = new JButton("取消");
+
+    setupButtonStyle(changeButton);
+    setupButtonStyle(cancelButton);
+
+    buttonPanel.add(changeButton);
+    buttonPanel.add(cancelButton);
+
+    // 添加组件到主面板
+    mainPanel.add(titleLabel, BorderLayout.NORTH);
+    mainPanel.add(formPanel, BorderLayout.CENTER);
+    mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+
+    add(mainPanel);
+
+    // 添加事件监听器
+    setupEventListeners();
+  }
+
+  private void setupButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.BOLD, 14));
+    button.setBackground(new Color(0, 120, 215));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
+  }
+
+  private void setupEventListeners() {
+    changeButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleChangePassword();
+      }
+    });
+
+    cancelButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        dispose();
+      }
+    });
+
+    // 回车键确认修改
+    confirmPasswordField.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleChangePassword();
+      }
+    });
+  }
+
+  private void handleChangePassword() {
+    String oldPassword = new String(oldPasswordField.getPassword());
+    String newPassword = new String(newPasswordField.getPassword());
+    String confirmPassword = new String(confirmPasswordField.getPassword());
+
+    if (oldPassword.isEmpty() || newPassword.isEmpty() || confirmPassword.isEmpty()) {
+      JOptionPane.showMessageDialog(this, "请填写所有字段", "输入错误", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+
+    String result = userManager.changePassword(currentUser.getEmail(), oldPassword, newPassword, confirmPassword);
+
+    if (result.equals("密码修改成功")) {
+      JOptionPane.showMessageDialog(this, result, "修改成功", JOptionPane.INFORMATION_MESSAGE);
+      dispose();
+    } else {
+      JOptionPane.showMessageDialog(this, result, "修改失败", JOptionPane.ERROR_MESSAGE);
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/frontend/LoginFrame.class b/src/frontend/LoginFrame.class
new file mode 100644
index 0000000..1840cde
Binary files /dev/null and b/src/frontend/LoginFrame.class differ
diff --git a/src/frontend/LoginFrame.java b/src/frontend/LoginFrame.java
new file mode 100644
index 0000000..9c96de7
--- /dev/null
+++ b/src/frontend/LoginFrame.java
@@ -0,0 +1,132 @@
+package frontend;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import backend.UserManager;
+import backend.User;
+
+public class LoginFrame extends JFrame {
+  private JTextField emailField;
+  private JPasswordField passwordField;
+  private JButton loginButton, registerButton;
+  private UserManager userManager;
+
+  public LoginFrame() {
+    userManager = UserManager.getInstance();
+    initializeUI();
+  }
+
+  private void initializeUI() {
+    setTitle("中小学数学学习软件 - 登录");
+    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    setSize(400, 300);
+    setLocationRelativeTo(null);
+    setResizable(false);
+
+    // 创建主面板
+    JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+    mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 标题
+    JLabel titleLabel = new JLabel("中小学数学学习软件", JLabel.CENTER);
+    titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 18));
+    titleLabel.setForeground(new Color(0, 120, 215));
+
+    // 表单面板
+    JPanel formPanel = new JPanel(new GridLayout(3, 2, 10, 10));
+
+    JLabel emailLabel = new JLabel("邮箱/用户名:");
+    emailLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    emailField = new JTextField();
+
+    JLabel passwordLabel = new JLabel("密码:");
+    passwordLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    passwordField = new JPasswordField();
+
+    formPanel.add(emailLabel);
+    formPanel.add(emailField);
+    formPanel.add(passwordLabel);
+    formPanel.add(passwordField);
+
+    // 按钮面板
+    JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
+    loginButton = new JButton("登录");
+    registerButton = new JButton("注册");
+
+    // 设置按钮样式
+    setupButtonStyle(loginButton);
+    setupButtonStyle(registerButton);
+
+    buttonPanel.add(loginButton);
+    buttonPanel.add(registerButton);
+
+    // 添加组件到主面板
+    mainPanel.add(titleLabel, BorderLayout.NORTH);
+    mainPanel.add(formPanel, BorderLayout.CENTER);
+    mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+
+    add(mainPanel);
+
+    // 添加事件监听器
+    setupEventListeners();
+  }
+
+  private void setupButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.BOLD, 14));
+    button.setBackground(new Color(0, 120, 215));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
+  }
+
+  private void setupEventListeners() {
+    loginButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleLogin();
+      }
+    });
+
+    registerButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleRegister();
+      }
+    });
+
+    // 回车键登录
+    passwordField.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleLogin();
+      }
+    });
+  }
+
+  private void handleLogin() {
+    String identifier = emailField.getText().trim();
+    String password = new String(passwordField.getPassword());
+
+    if (identifier.isEmpty() || password.isEmpty()) {
+      JOptionPane.showMessageDialog(this, "请输入邮箱/用户名和密码", "输入错误", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+
+    User user = userManager.authenticate(identifier, password);
+    if (user != null) {
+      // 登录成功，打开主界面
+      dispose(); // 关闭登录窗口
+      new MainFrame(user).setVisible(true);
+    } else {
+      JOptionPane.showMessageDialog(this, "邮箱/用户名或密码错误", "登录失败", JOptionPane.ERROR_MESSAGE);
+    }
+  }
+
+  private void handleRegister() {
+    new RegistrationFrame(this).setVisible(true);
+  }
+
+
+}
\ No newline at end of file
diff --git a/src/frontend/MainFrame.class b/src/frontend/MainFrame.class
new file mode 100644
index 0000000..e365ab2
Binary files /dev/null and b/src/frontend/MainFrame.class differ
diff --git a/src/frontend/MainFrame.java b/src/frontend/MainFrame.java
new file mode 100644
index 0000000..d236bb3
--- /dev/null
+++ b/src/frontend/MainFrame.java
@@ -0,0 +1,157 @@
+package frontend;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import backend.User;
+import backend.UserManager;
+
+public class MainFrame extends JFrame {
+  private User currentUser;
+  private JButton primarySchoolButton, middleSchoolButton, highSchoolButton;
+  private JButton changePasswordButton, logoutButton;
+  private UserManager userManager;
+
+  public MainFrame(User user) {
+    this.currentUser = user;
+    this.userManager = UserManager.getInstance();
+    initializeUI();
+  }
+
+  private void initializeUI() {
+    setTitle("中小学数学学习软件 - 主界面");
+    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    setSize(500, 400);
+    setLocationRelativeTo(null);
+    setResizable(false);
+
+    // 创建主面板
+    JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+    mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 欢迎面板
+    JPanel welcomePanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
+    JLabel welcomeLabel = new JLabel("欢迎使用中小学数学学习软件", JLabel.CENTER);
+    welcomeLabel.setFont(new Font("微软雅黑", Font.BOLD, 16));
+    welcomeLabel.setForeground(new Color(0, 120, 215));
+    welcomePanel.add(welcomeLabel);
+
+    // 用户信息面板
+    JPanel userInfoPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
+    JLabel userInfoLabel = new JLabel("当前用户: " + currentUser.getUsername(), JLabel.CENTER);
+    userInfoLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    userInfoPanel.add(userInfoLabel);
+
+    // 学校选择面板
+    JPanel schoolPanel = new JPanel(new GridLayout(3, 1, 15, 15));
+    schoolPanel.setBorder(BorderFactory.createTitledBorder("请选择学校类型"));
+
+    primarySchoolButton = new JButton("小学");
+    middleSchoolButton = new JButton("初中");
+    highSchoolButton = new JButton("高中");
+
+    setupSchoolButtonStyle(primarySchoolButton);
+    setupSchoolButtonStyle(middleSchoolButton);
+    setupSchoolButtonStyle(highSchoolButton);
+
+    schoolPanel.add(primarySchoolButton);
+    schoolPanel.add(middleSchoolButton);
+    schoolPanel.add(highSchoolButton);
+
+    // 功能按钮面板
+    JPanel functionPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
+    changePasswordButton = new JButton("修改密码");
+    logoutButton = new JButton("退出登录");
+
+    setupFunctionButtonStyle(changePasswordButton);
+    setupFunctionButtonStyle(logoutButton);
+
+    functionPanel.add(changePasswordButton);
+    functionPanel.add(logoutButton);
+
+    // 添加组件到主面板
+    mainPanel.add(welcomePanel, BorderLayout.NORTH);
+    mainPanel.add(userInfoPanel, BorderLayout.CENTER);
+    mainPanel.add(schoolPanel, BorderLayout.CENTER);
+    mainPanel.add(functionPanel, BorderLayout.SOUTH);
+
+    add(mainPanel);
+
+    // 添加事件监听器
+    setupEventListeners();
+  }
+
+  private void setupSchoolButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.BOLD, 16));
+    button.setBackground(new Color(70, 130, 180));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(15, 30, 15, 30));
+  }
+
+  private void setupFunctionButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.PLAIN, 12));
+    button.setBackground(new Color(169, 169, 169));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(5, 15, 5, 15));
+  }
+
+  private void setupEventListeners() {
+    primarySchoolButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleSchoolSelection("小学");
+      }
+    });
+
+    middleSchoolButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleSchoolSelection("初中");
+      }
+    });
+
+    highSchoolButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleSchoolSelection("高中");
+      }
+    });
+
+    changePasswordButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        new ChangePasswordFrame(MainFrame.this, currentUser).setVisible(true);
+      }
+    });
+
+    logoutButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleLogout();
+      }
+    });
+  }
+
+  private void handleSchoolSelection(String schoolType) {
+    // 设置用户类型
+    userManager.setUserType(currentUser.getEmail(), schoolType);
+    currentUser.setUserType(schoolType);
+
+    // 打开题目数量输入界面
+    new QuestionCountFrame(this, currentUser).setVisible(true);
+  }
+
+  private void handleLogout() {
+    int result = JOptionPane.showConfirmDialog(this,
+        "确定要退出登录吗？", "确认退出",
+        JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE);
+
+    if (result == JOptionPane.YES_OPTION) {
+      dispose();
+      new LoginFrame().setVisible(true);
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/frontend/QuestionCountFrame.class b/src/frontend/QuestionCountFrame.class
new file mode 100644
index 0000000..0c7a3e0
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diff --git a/src/frontend/QuestionCountFrame.java b/src/frontend/QuestionCountFrame.java
new file mode 100644
index 0000000..d611106
--- /dev/null
+++ b/src/frontend/QuestionCountFrame.java
@@ -0,0 +1,134 @@
+package frontend;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import backend.User;
+
+public class QuestionCountFrame extends JFrame {
+  private JTextField countField;
+  private JButton startButton, backButton;
+  private User currentUser;
+  private MainFrame mainFrame;
+
+  public QuestionCountFrame(MainFrame mainFrame, User user) {
+    this.mainFrame = mainFrame;
+    this.currentUser = user;
+    initializeUI();
+  }
+
+  private void initializeUI() {
+    setTitle("题目数量设置 - " + currentUser.getUserType());
+    setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+    setSize(400, 250);
+    setLocationRelativeTo(mainFrame);
+    setResizable(false);
+
+    // 创建主面板
+    JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+    mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 标题
+    JLabel titleLabel = new JLabel("请输入题目数量", JLabel.CENTER);
+    titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 16));
+    titleLabel.setForeground(new Color(0, 120, 215));
+
+    // 信息标签
+    JLabel infoLabel = new JLabel("当前选择: " + currentUser.getUserType(), JLabel.CENTER);
+    infoLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+
+    // 输入面板
+    JPanel inputPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
+    JLabel countLabel = new JLabel("题目数量:");
+    countLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    countField = new JTextField(10);
+    countField.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+
+    inputPanel.add(countLabel);
+    inputPanel.add(countField);
+
+    // 按钮面板
+    JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
+    startButton = new JButton("开始答题");
+    backButton = new JButton("返回");
+
+    setupButtonStyle(startButton);
+    setupButtonStyle(backButton);
+
+    buttonPanel.add(startButton);
+    buttonPanel.add(backButton);
+
+    // 添加组件到主面板
+    mainPanel.add(titleLabel, BorderLayout.NORTH);
+    mainPanel.add(infoLabel, BorderLayout.CENTER);
+    mainPanel.add(inputPanel, BorderLayout.CENTER);
+    mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+
+    add(mainPanel);
+
+    // 添加事件监听器
+    setupEventListeners();
+  }
+
+  private void setupButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.BOLD, 14));
+    button.setBackground(new Color(0, 120, 215));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
+  }
+
+  private void setupEventListeners() {
+    startButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleStartQuiz();
+      }
+    });
+
+    backButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        dispose();
+      }
+    });
+
+    // 回车键开始答题
+    countField.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleStartQuiz();
+      }
+    });
+  }
+
+  private void handleStartQuiz() {
+    String countText = countField.getText().trim();
+
+    if (countText.isEmpty()) {
+      JOptionPane.showMessageDialog(this, "请输入题目数量", "输入错误", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+
+    try {
+      int count = Integer.parseInt(countText);
+      if (count <= 0) {
+        JOptionPane.showMessageDialog(this, "题目数量必须大于0", "输入错误", JOptionPane.WARNING_MESSAGE);
+        return;
+      }
+
+      if (count > 50) {
+        JOptionPane.showMessageDialog(this, "题目数量不能超过50", "输入错误", JOptionPane.WARNING_MESSAGE);
+        return;
+      }
+
+      // 创建答题界面
+      dispose();
+      new QuizFrame(mainFrame, currentUser, count).setVisible(true);
+
+    } catch (NumberFormatException e) {
+      JOptionPane.showMessageDialog(this, "请输入有效的数字", "输入错误", JOptionPane.WARNING_MESSAGE);
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/frontend/QuizFrame.class b/src/frontend/QuizFrame.class
new file mode 100644
index 0000000..fd08b88
Binary files /dev/null and b/src/frontend/QuizFrame.class differ
diff --git a/src/frontend/QuizFrame.java b/src/frontend/QuizFrame.java
new file mode 100644
index 0000000..0e69455
--- /dev/null
+++ b/src/frontend/QuizFrame.java
@@ -0,0 +1,271 @@
+package frontend;
+
+import backend.MathCalculator;
+import backend.QuestionGenerator;
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.util.ArrayList;
+import java.util.List;
+import backend.User;
+import backend.Question;
+import backend.PrimarySchoolGenerator;
+import backend.MiddleSchoolGenerator;
+import backend.HighSchoolGenerator;
+
+public class QuizFrame extends JFrame {
+  private User currentUser;
+  private MainFrame mainFrame;
+  private int totalQuestions;
+  private int currentQuestionIndex;
+  private List<Question> questions;
+  private List<String> userAnswers;
+
+  // UI组件
+  private JLabel questionNumberLabel;
+  private JTextArea questionTextArea;
+  private JRadioButton[] optionButtons;
+  private ButtonGroup optionGroup;
+  private JButton nextButton, submitButton;
+  private JPanel optionsPanel;
+
+  public QuizFrame(MainFrame mainFrame, User user, int totalQuestions) {
+    this.mainFrame = mainFrame;
+    this.currentUser = user;
+    this.totalQuestions = totalQuestions;
+    this.currentQuestionIndex = 0;
+    this.questions = generateQuestions();
+    this.userAnswers = new ArrayList<>();
+
+    initializeUI();
+    showQuestion(0);
+  }
+
+  private void initializeUI() {
+    setTitle("数学答题 - " + currentUser.getUserType());
+    setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
+    setSize(600, 500);
+    setLocationRelativeTo(mainFrame);
+    setResizable(false);
+
+    // 创建主面板
+    JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+    mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 题目编号标签
+    questionNumberLabel = new JLabel("", JLabel.CENTER);
+    questionNumberLabel.setFont(new Font("微软雅黑", Font.BOLD, 16));
+    questionNumberLabel.setForeground(new Color(0, 120, 215));
+
+    // 题目文本区域
+    questionTextArea = new JTextArea();
+    questionTextArea.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    questionTextArea.setLineWrap(true);
+    questionTextArea.setWrapStyleWord(true);
+    questionTextArea.setEditable(false);
+    questionTextArea.setFocusable(false); // 设置为不可获得焦点，移除光标
+    questionTextArea.setBackground(UIManager.getColor("Panel.background"));
+    questionTextArea.setBorder(null); // 移除边框
+
+    // 选项面板
+    optionsPanel = new JPanel(new GridLayout(4, 1, 10, 10));
+    optionButtons = new JRadioButton[4];
+    optionGroup = new ButtonGroup();
+
+    for (int i = 0; i < 4; i++) {
+      optionButtons[i] = new JRadioButton();
+      optionButtons[i].setFont(new Font("微软雅黑", Font.PLAIN, 14));
+      optionGroup.add(optionButtons[i]);
+      optionsPanel.add(optionButtons[i]);
+    }
+
+    // 按钮面板
+    JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
+    nextButton = new JButton("下一题");
+    submitButton = new JButton("提交答案");
+    submitButton.setVisible(false);
+
+    setupButtonStyle(nextButton);
+    setupButtonStyle(submitButton);
+
+    buttonPanel.add(nextButton);
+    buttonPanel.add(submitButton);
+
+    // 添加组件到主面板
+    mainPanel.add(questionNumberLabel, BorderLayout.NORTH);
+
+    // 创建中间面板来容纳题目文本和选项
+    JPanel centerPanel = new JPanel(new BorderLayout(10, 10));
+    // 创建JScrollPane并设置无边框
+    JScrollPane scrollPane = new JScrollPane(questionTextArea);
+    scrollPane.setBorder(null); // 移除滚动面板的边框
+    centerPanel.add(scrollPane, BorderLayout.NORTH);
+    centerPanel.add(optionsPanel, BorderLayout.CENTER);
+
+    mainPanel.add(centerPanel, BorderLayout.CENTER);
+    mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+
+    add(mainPanel);
+
+    // 添加事件监听器
+    setupEventListeners();
+  }
+
+  private void setupButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.BOLD, 14));
+    button.setBackground(new Color(0, 120, 215));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
+  }
+
+  private void setupEventListeners() {
+    nextButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleNextQuestion();
+      }
+    });
+
+    submitButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleSubmitQuiz();
+      }
+    });
+  }
+
+  private void showQuestion(int index) {
+    if (index >= questions.size()) {
+      return;
+    }
+
+    Question question = questions.get(index);
+    //System.out.println(question.getQuestionText());
+
+    // 更新题目编号
+    questionNumberLabel.setText("第 " + (index + 1) + " 题 / 共 " + totalQuestions + " 题");
+
+    // 更新题目文本
+    questionTextArea.setText(question.getQuestionText());
+
+    // 更新选项
+    String[] options = question.getOptions();
+    for (int i = 0; i < 4; i++) {
+      if (i < options.length) {
+        optionButtons[i].setText(options[i]);
+        optionButtons[i].setVisible(true);
+      } else {
+        optionButtons[i].setVisible(false);
+      }
+    }
+
+    // 清除选择
+    optionGroup.clearSelection();
+
+    // 更新按钮状态
+    if (index == totalQuestions - 1) {
+      nextButton.setVisible(false);
+      submitButton.setVisible(true);
+    } else {
+      nextButton.setVisible(true);
+      submitButton.setVisible(false);
+    }
+  }
+
+  private void handleNextQuestion() {
+    // 获取当前选择的答案
+    String selectedAnswer = getSelectedAnswer();
+    if (selectedAnswer == null) {
+      JOptionPane.showMessageDialog(this, "请选择一个答案", "提示", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+
+    // 保存答案
+    userAnswers.add(selectedAnswer);
+
+    // 显示下一题
+    currentQuestionIndex++;
+    showQuestion(currentQuestionIndex);
+  }
+
+  private void handleSubmitQuiz() {
+    // 获取最后一题的答案
+    String selectedAnswer = getSelectedAnswer();
+    if (selectedAnswer == null) {
+      JOptionPane.showMessageDialog(this, "请选择一个答案", "提示", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+
+    // 保存最后一题的答案
+    userAnswers.add(selectedAnswer);
+
+    // 计算分数
+    int correctCount = 0;
+    for (int i = 0; i < questions.size(); i++) {
+      if (i < userAnswers.size() && questions.get(i).isCorrect(userAnswers.get(i))) {
+        correctCount++;
+      }
+    }
+
+    double score = (double) correctCount / totalQuestions * 100;
+
+    // 显示分数界面
+    dispose();
+    new ScoreFrame(mainFrame, currentUser, score, totalQuestions, correctCount).setVisible(true);
+  }
+
+  private String getSelectedAnswer() {
+    for (int i = 0; i < 4; i++) {
+      if (optionButtons[i].isSelected()) {
+        return optionButtons[i].getText();
+      }
+    }
+    return null;
+  }
+
+  private List<Question> generateQuestions() {
+    List<Question> questionList = new ArrayList<>();
+    QuestionGenerator generator = createQuestionGenerator();
+
+    for (int i = 0; i < totalQuestions; i++) {
+      // 生成纯数学表达式
+      String expression = generator.generateQuestion();
+
+      // 获取当前级别的题目描述
+      String description = generator.getQuestionDescription();
+
+      // 组合题目描述和数学表达式作为完整题目
+      String questionText = description + expression;
+
+      // 计算题目的答案（使用纯数学表达式）
+      String correctAnswer = calculateAnswer(expression);
+      String[] options = generator.generateOptions(correctAnswer);
+
+      // 创建Question对象，使用包含描述的完整题目和正确答案
+      Question question = new Question(questionText, options, correctAnswer);
+      questionList.add(question);
+    }
+
+    return questionList;
+  }
+
+  private QuestionGenerator createQuestionGenerator() {
+    switch (currentUser.getUserType()) {
+      case "小学":
+        return new PrimarySchoolGenerator();
+      case "初中":
+        return new MiddleSchoolGenerator();
+      case "高中":
+        return new HighSchoolGenerator();
+      default:
+        return new PrimarySchoolGenerator();
+    }
+  }
+
+  private String calculateAnswer(String questionText) {
+    // 使用MathCalculator计算数学表达式的结果
+    return MathCalculator.calculateSimple(questionText);
+  }
+}
\ No newline at end of file
diff --git a/src/frontend/RegistrationFrame.class b/src/frontend/RegistrationFrame.class
new file mode 100644
index 0000000..b41de4f
Binary files /dev/null and b/src/frontend/RegistrationFrame.class differ
diff --git a/src/frontend/RegistrationFrame.java b/src/frontend/RegistrationFrame.java
new file mode 100644
index 0000000..7f2cdde
--- /dev/null
+++ b/src/frontend/RegistrationFrame.java
@@ -0,0 +1,194 @@
+package frontend;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import backend.UserManager;
+
+public class RegistrationFrame extends JFrame {
+  private JTextField emailField;
+  private JTextField usernameField;
+  private JTextField verificationCodeField;
+  private JPasswordField passwordField;
+  private JPasswordField confirmPasswordField;
+  private JButton sendCodeButton, registerButton, backButton;
+  private UserManager userManager;
+  private LoginFrame loginFrame;
+
+  public RegistrationFrame(LoginFrame loginFrame) {
+    this.loginFrame = loginFrame;
+    this.userManager = UserManager.getInstance();
+    initializeUI();
+  }
+
+  private void initializeUI() {
+    setTitle("用户注册");
+    setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+    setSize(450, 400);
+    setLocationRelativeTo(loginFrame);
+    setResizable(false);
+
+    // 创建主面板
+    JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+    mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 标题
+    JLabel titleLabel = new JLabel("用户注册", JLabel.CENTER);
+    titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 18));
+    titleLabel.setForeground(new Color(0, 120, 215));
+
+    // 表单面板
+    JPanel formPanel = new JPanel(new GridLayout(6, 2, 10, 15));
+
+    JLabel emailLabel = new JLabel("邮箱:");
+    emailLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    emailField = new JTextField();
+
+    JLabel usernameLabel = new JLabel("用户名:");
+    usernameLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    usernameField = new JTextField();
+
+    JLabel codeLabel = new JLabel("验证码:");
+    codeLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    verificationCodeField = new JTextField();
+
+    JLabel passwordLabel = new JLabel("密码:");
+    passwordLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    passwordField = new JPasswordField();
+
+    JLabel confirmPasswordLabel = new JLabel("确认密码:");
+    confirmPasswordLabel.setFont(new Font("微软雅黑", Font.PLAIN, 14));
+    confirmPasswordField = new JPasswordField();
+
+    // 发送验证码按钮
+    sendCodeButton = new JButton("发送验证码");
+    setupButtonStyle(sendCodeButton);
+
+    formPanel.add(emailLabel);
+    formPanel.add(emailField);
+    formPanel.add(usernameLabel);
+    formPanel.add(usernameField);
+    formPanel.add(codeLabel);
+    formPanel.add(verificationCodeField);
+    formPanel.add(new JLabel()); // 空标签占位
+    formPanel.add(sendCodeButton);
+    formPanel.add(passwordLabel);
+    formPanel.add(passwordField);
+    formPanel.add(confirmPasswordLabel);
+    formPanel.add(confirmPasswordField);
+
+    // 按钮面板
+    JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
+    registerButton = new JButton("注册");
+    backButton = new JButton("返回登录");
+
+    setupButtonStyle(registerButton);
+    setupButtonStyle(backButton);
+
+    buttonPanel.add(registerButton);
+    buttonPanel.add(backButton);
+
+    // 添加组件到主面板
+    mainPanel.add(titleLabel, BorderLayout.NORTH);
+    mainPanel.add(formPanel, BorderLayout.CENTER);
+    mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+
+    add(mainPanel);
+
+    // 添加事件监听器
+    setupEventListeners();
+  }
+
+  private void setupButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.BOLD, 14));
+    button.setBackground(new Color(0, 120, 215));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
+  }
+
+  private void setupEventListeners() {
+    sendCodeButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleSendVerificationCode();
+      }
+    });
+
+    registerButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleRegister();
+      }
+    });
+
+    backButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        dispose();
+        loginFrame.setVisible(true);
+      }
+    });
+
+    // 回车键注册
+    confirmPasswordField.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        handleRegister();
+      }
+    });
+  }
+
+  private void handleSendVerificationCode() {
+    String email = emailField.getText().trim();
+    String username = usernameField.getText().trim();
+
+    if (email.isEmpty()) {
+      JOptionPane.showMessageDialog(this, "请输入邮箱地址", "输入错误", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+    
+    if (username.isEmpty()) {
+      JOptionPane.showMessageDialog(this, "请输入用户名", "输入错误", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+    
+    // 检查用户名是否已被注册
+    if (userManager.isUsernameRegistered(username)) {
+      JOptionPane.showMessageDialog(this, "该用户名已被注册", "注册失败", JOptionPane.ERROR_MESSAGE);
+      return;
+    }
+
+    // 调用UserManager发送验证码
+    String result = userManager.sendVerificationCode(email);
+
+    // 显示发送结果
+    JOptionPane.showMessageDialog(this, result, "验证码发送", JOptionPane.INFORMATION_MESSAGE);
+  }
+
+  private void handleRegister() {
+    String email = emailField.getText().trim();
+    String username = usernameField.getText().trim();
+    String verificationCode = verificationCodeField.getText().trim();
+    String password = new String(passwordField.getPassword());
+    String confirmPassword = new String(confirmPasswordField.getPassword());
+
+    // 基本的非空检查
+    if (email.isEmpty() || username.isEmpty() || verificationCode.isEmpty() || password.isEmpty() || confirmPassword.isEmpty()) {
+      JOptionPane.showMessageDialog(this, "请填写所有字段", "输入错误", JOptionPane.WARNING_MESSAGE);
+      return;
+    }
+
+    // 用户名的具体验证逻辑已在UserManager.registerUser方法中实现（在验证码验证之后）
+    String result = userManager.registerUser(email, username, verificationCode, password, confirmPassword);
+
+    if (result.equals("注册成功")) {
+      JOptionPane.showMessageDialog(this, result, "注册成功", JOptionPane.INFORMATION_MESSAGE);
+      dispose();
+      loginFrame.setVisible(true);
+    } else {
+      JOptionPane.showMessageDialog(this, result, "注册失败", JOptionPane.ERROR_MESSAGE);
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/frontend/ScoreFrame.class b/src/frontend/ScoreFrame.class
new file mode 100644
index 0000000..f94d5df
Binary files /dev/null and b/src/frontend/ScoreFrame.class differ
diff --git a/src/frontend/ScoreFrame.java b/src/frontend/ScoreFrame.java
new file mode 100644
index 0000000..39a06b4
--- /dev/null
+++ b/src/frontend/ScoreFrame.java
@@ -0,0 +1,155 @@
+package frontend;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import backend.User;
+
+public class ScoreFrame extends JFrame {
+  private User currentUser;
+  private MainFrame mainFrame;
+  private double score;
+  private int totalQuestions;
+  private int correctCount;
+
+  public ScoreFrame(MainFrame mainFrame, User user, double score, int totalQuestions, int correctCount) {
+    this.mainFrame = mainFrame;
+    this.currentUser = user;
+    this.score = score;
+    this.totalQuestions = totalQuestions;
+    this.correctCount = correctCount;
+    initializeUI();
+  }
+
+  private void initializeUI() {
+    setTitle("答题结果");
+    setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+    setSize(500, 400);
+    setLocationRelativeTo(mainFrame);
+    setResizable(false);
+
+    // 创建主面板
+    JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
+    mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 标题
+    JLabel titleLabel = new JLabel("答题完成", JLabel.CENTER);
+    titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 20));
+    titleLabel.setForeground(new Color(0, 120, 215));
+
+    // 分数显示面板
+    JPanel scorePanel = new JPanel(new GridLayout(4, 1, 10, 10));
+    scorePanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
+
+    // 分数显示
+    JLabel scoreLabel = new JLabel(String.format("得分: %.1f分", score), JLabel.CENTER);
+    scoreLabel.setFont(new Font("微软雅黑", Font.BOLD, 24));
+    scoreLabel.setForeground(getScoreColor(score));
+
+    // 详细信息
+    JLabel detailLabel = new JLabel(
+        String.format("答对 %d 题，共 %d 题", correctCount, totalQuestions),
+        JLabel.CENTER
+    );
+    detailLabel.setFont(new Font("微软雅黑", Font.PLAIN, 16));
+
+    // 百分比
+    JLabel percentageLabel = new JLabel(
+        String.format("正确率: %.1f%%", score),
+        JLabel.CENTER
+    );
+    percentageLabel.setFont(new Font("微软雅黑", Font.PLAIN, 16));
+
+    // 评价
+    JLabel commentLabel = new JLabel(getScoreComment(score), JLabel.CENTER);
+    commentLabel.setFont(new Font("微软雅黑", Font.ITALIC, 14));
+    commentLabel.setForeground(Color.GRAY);
+
+    scorePanel.add(scoreLabel);
+    scorePanel.add(detailLabel);
+    scorePanel.add(percentageLabel);
+    scorePanel.add(commentLabel);
+
+    // 按钮面板
+    JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
+    JButton continueButton = new JButton("继续做题");
+    JButton exitButton = new JButton("退出");
+
+    setupButtonStyle(continueButton);
+    setupButtonStyle(exitButton);
+
+    buttonPanel.add(continueButton);
+    buttonPanel.add(exitButton);
+
+    // 添加组件到主面板
+    mainPanel.add(titleLabel, BorderLayout.NORTH);
+    mainPanel.add(scorePanel, BorderLayout.CENTER);
+    mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+
+    add(mainPanel);
+
+    // 添加事件监听器
+    setupEventListeners(continueButton, exitButton);
+  }
+
+  private void setupButtonStyle(JButton button) {
+    button.setFont(new Font("微软雅黑", Font.BOLD, 14));
+    button.setBackground(new Color(0, 120, 215));
+    button.setForeground(Color.BLACK);
+    button.setFocusPainted(false);
+    button.setBorder(BorderFactory.createEmptyBorder(10, 20, 10, 20));
+  }
+
+  private void setupEventListeners(JButton continueButton, JButton exitButton) {
+    continueButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        // 返回主界面，用户可以重新选择学校类型
+        dispose();
+        mainFrame.setVisible(true);
+      }
+    });
+
+    exitButton.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        int result = JOptionPane.showConfirmDialog(
+            ScoreFrame.this,
+            "确定要退出程序吗？",
+            "确认退出",
+            JOptionPane.YES_NO_OPTION,
+            JOptionPane.QUESTION_MESSAGE
+        );
+
+        if (result == JOptionPane.YES_OPTION) {
+          System.exit(0);
+        }
+      }
+    });
+  }
+
+  private Color getScoreColor(double score) {
+    if (score >= 90) {
+      return new Color(0, 150, 0); // 绿色 - 优秀
+    } else if (score >= 70) {
+      return new Color(255, 165, 0); // 橙色 - 良好
+    } else if (score >= 60) {
+      return new Color(255, 215, 0); // 金色 - 及格
+    } else {
+      return new Color(220, 20, 60); // 红色 - 不及格
+    }
+  }
+
+  private String getScoreComment(double score) {
+    if (score >= 90) {
+      return "太棒了！继续保持！";
+    } else if (score >= 70) {
+      return "做得不错，继续努力！";
+    } else if (score >= 60) {
+      return "及格了，再加把劲！";
+    } else {
+      return "需要多加练习哦！";
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/registry.dat b/src/registry.dat
new file mode 100644
index 0000000..d7abc22
Binary files /dev/null and b/src/registry.dat differ