修复题目生成逻辑：确保操作数数量符合要求

- 小学题目：操作数至少为2个，避免出现单个操作数题目
- 初中题目：操作数可以为1个（涉及平方、开根号运算）
- 高中题目：操作数可以为1个（涉及三角函数运算）
- 添加题目验证逻辑，确保生成的题目符合难度要求
- 优化题目生成算法，增加题目多样性

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>

exams/张三1/2025-09-28-20-12-09.txt

@@ -0,0 +1,29 @@
+1. 58 = 
+
+2. 19 / 81 = 
+
+3. 77 - 20 = 
+
+4. (66 + 65 + 35 / 57) = 
+
+5. 29 / 37 = 
+
+6. (64 / 31) - 27 * 64 - 69 = 
+
+7. ((97) * 83 * 39 + 23) = 
+
+8. 72 - 85 = 
+
+9. 30 - 79 + 63 + 82 = 
+
+10. 95 - 26 = 
+
+11. 13 - 98 = 
+
+12. 36 - 55 = 
+
+13. (((94 + 72) * 1) * 13) / 90 = 
+
+14. 36 * 69 = 
+
+15. (68 + 60) * 65 / 33 = 

exams/张三1/2025-09-28-23-06-51.txt

@@ -0,0 +1,31 @@
+1. 69 = 
+
+2. (4 + 49 - 36 + 79) = 
+
+3. 17 = 
+
+4. ((83 + 61 - 26) + 24 * 93) = 
+
+5. 65 = 
+
+6. 16 / 66 = 
+
+7. 5 / 93 = 
+
+8. 33 / 11 = 
+
+9. 91 = 
+
+10. (22 - 13) + 70 + 40 / 59 = 
+
+11. 88 = 
+
+12. ((87) + 89) - 55 * 76 = 
+
+13. 63 + 18 + 6 - 25 = 
+
+14. 44 / 37 - 45 - 87 = 
+
+15. ((74) + 53) / 31 / 54 = 
+
+16. 91 / 9 + 55 * 38 = 

exams/李四1/2025-09-28-23-39-02.txt

@@ -0,0 +1,39 @@
+1. (9)² = 
+
+2. √99 = 
+
+3. (5)² = 
+
+4. √86 + (39) + 56 / 86 = 
+
+5. √44 + ((21) * 49) / 19 / 15 / 6 = 
+
+6. (4)² = 
+
+7. (7)² = 
+
+8. (5)² + (36 - 53 + 24) = 
+
+9. √27 = 
+
+10. (2)² = 
+
+11. (6)² + ((30) / 29 / 87) * 6 + 49 = 
+
+12. √54 = 
+
+13. √73 = 
+
+14. (5)² + 14 * 89 / 65 / 6 - 16 = 
+
+15. √55 = 
+
+16. √74 + (((16) - 29) * 26 - 34) = 
+
+17. √11 = 
+
+18. √41 + ((71) / 57 - 16 * 8) + 90 = 
+
+19. (6)² = 
+
+20. √63 = 

exams/王五1/2025-09-28-23-36-24.txt

@@ -0,0 +1,39 @@
+1. sin(67°) + ((91) - 77) + 2 = 
+
+2. cos(40°) + (88) / 44 + 69 + 17 + 93 = 
+
+3. sin(20°) + 84 + 3 = 
+
+4. tan(16°) + 31 * 7 + 87 + 64 = 
+
+5. tan(18°) + (((24 - 34) - 27 * 58) * 67) = 
+
+6. cos(26°) + ((77 - 15 * 79) / 14 - 19) = 
+
+7. sin(24°) + 71 = 
+
+8. tan(14°) + 28 + 83 = 
+
+9. sin(7°) + (84) / 54 / 48 / 64 + 39 = 
+
+10. cos(21°) + 66 = 
+
+11. sin(33°) + 53 = 
+
+12. cos(37°) + 93 + 83 / 50 / 6 = 
+
+13. sin(38°) + (86 / 53 / 19 * 31) = 
+
+14. sin(48°) + 8 / 18 = 
+
+15. cos(83°) + 53 + 99 = 
+
+16. cos(73°) + 28 / 36 = 
+
+17. cos(10°) + 13 - 13 = 
+
+18. cos(83°) + 2 = 
+
+19. tan(35°) + (83) * 31 / 11 - 93 = 
+
+20. tan(26°) + (((53 + 63) + 74) + 22 / 58) = 

src/Main.java

@@ -1,31 +1,45 @@
+import interfaces.LoginSystemInterface;
+import interfaces.FileManagerInterface;
+import models.User;
+import models.DifficultyLevel;
+import factories.ServiceFactory;
+import services.QuestionGenerator;
 import java.util.Scanner;
 
 public class Main {
     public static void main(String[] args) {
         Scanner scanner = new Scanner(System.in);
-        LoginSystem loginSystem = new LoginSystem();
+
+        LoginSystemInterface loginSystem = ServiceFactory.createLoginSystem();
         QuestionGenerator generator = new QuestionGenerator();
-        FileManager fileManager = new FileManager();
+        FileManagerInterface fileManager = ServiceFactory.createFileManager();
 
         while (true) {
-            // 登录阶段
-            User currentUser = loginSystem.login(scanner);
+            System.out.print("请输入用户名和密码（用空格隔开）：");
+            String input = scanner.nextLine().trim();
+            String[] parts = input.split("\\s+");
+
+            if (parts.length != 2) {
+                System.out.println("请输入正确的用户名、密码");
+                continue;
+            }
+
+            User currentUser = loginSystem.login(parts[0], parts[1]);
             if (currentUser == null) {
+                System.out.println("请输入正确的用户名、密码");
                 continue;
             }
 
             System.out.println("当前选择为" + currentUser.getLevel().getDisplayName() + "出题");
 
-            // 主循环
             while (true) {
                 System.out.println("准备生成" + currentUser.getLevel().getDisplayName() +
                         "数学题目，请输入生成题目数量（输入-1将退出当前用户，重新登录）");
 
-                String input = scanner.nextLine().trim();
+                String command = scanner.nextLine().trim();
 
-                // 检查切换命令
-                if (input.startsWith("切换为")) {
-                    String levelName = input.substring(3).trim();
+                if (command.startsWith("切换为")) {
+                    String levelName = command.substring(3).trim();
                     DifficultyLevel newLevel = loginSystem.switchLevel(levelName);
                     if (newLevel != null) {
                         currentUser.setLevel(newLevel);
@@ -35,21 +49,18 @@ public class Main {
                     }
                 }
 
-                // 检查退出命令
-                if (input.equals("-1")) {
+                if (command.equals("-1")) {
                     System.out.println("退出当前用户，重新登录...");
                     break;
                 }
 
-                // 生成题目
                 try {
-                    int count = Integer.parseInt(input);
+                    int count = Integer.parseInt(command);
                     if (count < 10 || count > 30) {
                         System.out.println("题目数量应在10-30之间");
                         continue;
                     }
 
-                    // 生成题目并检查重复
                     String[] questions = generator.generateQuestions(currentUser.getLevel(), count,
                             currentUser.getUsername());
                     if (questions == null) {
@@ -57,7 +68,6 @@ public class Main {
                         continue;
                     }
 
-                    // 保存文件
                     boolean success = fileManager.saveQuestions(currentUser, questions);
                     if (success) {
                         System.out.println("题目生成成功！");

src/Question.java

@@ -1,4 +0,0 @@
-public interface Question {
-    String generateQuestion();
-    boolean isValid();
-}

src/QuestionGenerator.java

@@ -1,96 +0,0 @@
-import java.util.HashSet;
-import java.util.Random;
-import java.util.Set;
-
-public class QuestionGenerator {
-    private Random random;
-    private FileManager fileManager;
-
-    public QuestionGenerator() {
-        random = new Random();
-        fileManager = new FileManager();
-    }
-
-    public String[] generateQuestions(DifficultyLevel level, int count, String username) {
-        Set<String> existingQuestions = fileManager.loadExistingQuestions(username);
-        Set<String> newQuestions = new HashSet<>();
-        String[] questions = new String[count];
-
-        for (int i = 0; i < count; i++) {
-            String question;
-            int attempts = 0;
-
-            do {
-                question = generateSingleQuestion(level, i + 1);
-                attempts++;
-                if (attempts > 100) {
-                    return null; // 避免无限循环
-                }
-            } while (existingQuestions.contains(question) || newQuestions.contains(question));
-
-            newQuestions.add(question);
-            questions[i] = question;
-        }
-
-        return questions;
-    }
-
-    private String generateSingleQuestion(DifficultyLevel level, int questionNumber) {
-        int operandCount = random.nextInt(5) + 1; // 1-5个操作数
-        StringBuilder question = new StringBuilder(questionNumber + ". ");
-
-        switch (level) {
-            case PRIMARY:
-                question.append(generatePrimaryQuestion(operandCount));
-                break;
-            case JUNIOR:
-                question.append(generateJuniorQuestion(operandCount));
-                break;
-            case SENIOR:
-                question.append(generateSeniorQuestion(operandCount));
-                break;
-        }
-
-        question.append(" = ");
-        return question.toString();
-    }
-
-    private String generatePrimaryQuestion(int operandCount) {
-        String[] operators = {"+", "-", "*", "/"};
-        StringBuilder question = new StringBuilder();
-
-        for (int i = 0; i < operandCount; i++) {
-            if (i > 0) {
-                question.append(" ").append(operators[random.nextInt(operators.length)]).append(" ");
-            }
-            question.append(random.nextInt(100) + 1);
-
-            // 随机添加括号（小学难度）
-            if (operandCount > 2 && random.nextDouble() < 0.3) {
-                question.insert(0, "(").append(")");
-            }
-        }
-
-        return question.toString();
-    }
-
-    private String generateJuniorQuestion(int operandCount) {
-        String question = generatePrimaryQuestion(operandCount);
-
-        // 确保至少有一个平方或开根号
-        if (random.nextBoolean()) {
-            return "√" + (random.nextInt(100) + 1) + " + " + question;
-        } else {
-            return "(" + (random.nextInt(10) + 1) + ")² + " + question;
-        }
-    }
-
-    private String generateSeniorQuestion(int operandCount) {
-        String question = generatePrimaryQuestion(operandCount);
-        String[] trigFunctions = {"sin", "cos", "tan"};
-
-        // 确保至少有一个三角函数
-        return trigFunctions[random.nextInt(trigFunctions.length)] +
-                "(" + (random.nextInt(90) + 1) + "°) + " + question;
-    }
-}

src/factories/ServiceFactory.java

@@ -0,0 +1,16 @@
+package factories;
+
+import interfaces.LoginSystemInterface;
+import interfaces.FileManagerInterface;
+import services.LoginSystem;
+import services.FileManager;
+
+public class ServiceFactory {
+    public static LoginSystemInterface createLoginSystem() {
+        return new LoginSystem();
+    }
+
+    public static FileManagerInterface createFileManager() {
+        return new FileManager();
+    }
+}

src/interfaces/FileManagerInterface.java

@@ -0,0 +1,9 @@
+package interfaces;
+
+import models.User;
+import java.util.Set;
+
+public interface FileManagerInterface {
+    boolean saveQuestions(User user, String[] questions);
+    Set<String> loadExistingQuestions(String username);
+}

src/interfaces/LoginSystemInterface.java

@@ -0,0 +1,9 @@
+package interfaces;
+
+import models.User;
+import models.DifficultyLevel;
+
+public interface LoginSystemInterface {
+    User login(String username, String password);
+    DifficultyLevel switchLevel(String levelName);
+}

src/interfaces/QuestionInterface.java

@@ -0,0 +1,10 @@
+package interfaces;
+
+import models.DifficultyLevel;
+
+public interface QuestionInterface {
+    String generateQuestion();
+    boolean isValid();
+    String getQuestionText();
+    DifficultyLevel getDifficulty();
+}

src/models/DifficultyLevel.java

@@ -1,24 +1,26 @@
-public enum DifficultyLevel {
-    PRIMARY("小学"),
-    JUNIOR("初中"),
-    SENIOR("高中");
-
-    private final String displayName;
-
-    DifficultyLevel(String displayName) {
-        this.displayName = displayName;
-    }
-
-    public String getDisplayName() {
-        return displayName;
-    }
-
-    public static DifficultyLevel fromString(String text) {
-        for (DifficultyLevel level : DifficultyLevel.values()) {
-            if (level.displayName.equals(text)) {
-                return level;
-            }
-        }
-        return null;
-    }
+package models;
+
+public enum DifficultyLevel {
+    PRIMARY("小学"),
+    JUNIOR("初中"),
+    SENIOR("高中");
+
+    private final String displayName;
+
+    DifficultyLevel(String displayName) {
+        this.displayName = displayName;
+    }
+
+    public String getDisplayName() {
+        return displayName;
+    }
+
+    public static DifficultyLevel fromString(String text) {
+        for (DifficultyLevel level : DifficultyLevel.values()) {
+            if (level.displayName.equals(text)) {
+                return level;
+            }
+        }
+        return null;
+    }
 }

src/models/User.java

@@ -1,17 +1,18 @@
-public class User {
-    private String username;
-    private String password;
-    private DifficultyLevel level;
-
-    public User(String username, String password, DifficultyLevel level) {
-        this.username = username;
-        this.password = password;
-        this.level = level;
-    }
-
-    // Getter 和 Setter 方法
-    public String getUsername() { return username; }
-    public String getPassword() { return password; }
-    public DifficultyLevel getLevel() { return level; }
-    public void setLevel(DifficultyLevel level) { this.level = level; }
+package models;
+
+public class User {
+    private String username;
+    private String password;
+    private DifficultyLevel level;
+
+    public User(String username, String password, DifficultyLevel level) {
+        this.username = username;
+        this.password = password;
+        this.level = level;
+    }
+
+    public String getUsername() { return username; }
+    public String getPassword() { return password; }
+    public DifficultyLevel getLevel() { return level; }
+    public void setLevel(DifficultyLevel level) { this.level = level; }
 }

src/services/FileManager.java

@@ -1,66 +1,68 @@
-import java.io.*;
-import java.nio.file.*;
-import java.text.SimpleDateFormat;
-import java.util.Date;
-import java.util.HashSet;
-import java.util.Set;
-
-public class FileManager {
-    private static final String BASE_DIR = "exams";
-
-    public boolean saveQuestions(User user, String[] questions) {
-        try {
-            // 创建用户目录
-            Path userDir = Paths.get(BASE_DIR, user.getUsername());
-            Files.createDirectories(userDir);
-
-            // 生成文件名
-            String timestamp = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss").format(new Date());
-            Path filePath = userDir.resolve(timestamp + ".txt");
-
-            // 写入文件
-            try (PrintWriter writer = new PrintWriter(Files.newBufferedWriter(filePath))) {
-                for (int i = 0; i < questions.length; i++) {
-                    writer.println(questions[i]);
-                    if (i < questions.length - 1) {
-                        writer.println(); // 题目之间空一行
-                    }
-                }
-            }
-
-            return true;
-        } catch (IOException e) {
-            e.printStackTrace();
-            return false;
-        }
-    }
-
-    public Set<String> loadExistingQuestions(String username) {
-        Set<String> questions = new HashSet<>();
-        Path userDir = Paths.get(BASE_DIR, username);
-
-        if (!Files.exists(userDir)) {
-            return questions;
-        }
-
-        try (DirectoryStream<Path> stream = Files.newDirectoryStream(userDir, "*.txt")) {
-            for (Path filePath : stream) {
-                try (BufferedReader reader = Files.newBufferedReader(filePath)) {
-                    String line;
-                    while ((line = reader.readLine()) != null) {
-                        if (line.trim().isEmpty() || !line.contains(".")) {
-                            continue;
-                        }
-                        // 提取题目内容（去掉题号）
-                        String question = line.substring(line.indexOf(".") + 1).trim();
-                        questions.add(question);
-                    }
-                }
-            }
-        } catch (IOException e) {
-            e.printStackTrace();
-        }
-
-        return questions;
-    }
+package services;
+
+import interfaces.FileManagerInterface;
+import models.User;
+import java.io.*;
+import java.nio.file.*;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.HashSet;
+import java.util.Set;
+
+public class FileManager implements FileManagerInterface {
+    private static final String BASE_DIR = "exams";
+
+    @Override
+    public boolean saveQuestions(User user, String[] questions) {
+        try {
+            Path userDir = Paths.get(BASE_DIR, user.getUsername());
+            Files.createDirectories(userDir);
+
+            String timestamp = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss").format(new Date());
+            Path filePath = userDir.resolve(timestamp + ".txt");
+
+            try (PrintWriter writer = new PrintWriter(Files.newBufferedWriter(filePath))) {
+                for (int i = 0; i < questions.length; i++) {
+                    writer.println(questions[i]);
+                    if (i < questions.length - 1) {
+                        writer.println();
+                    }
+                }
+            }
+
+            return true;
+        } catch (IOException e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+
+    @Override
+    public Set<String> loadExistingQuestions(String username) {
+        Set<String> questions = new HashSet<>();
+        Path userDir = Paths.get(BASE_DIR, username);
+
+        if (!Files.exists(userDir)) {
+            return questions;
+        }
+
+        try (DirectoryStream<Path> stream = Files.newDirectoryStream(userDir, "*.txt")) {
+            for (Path filePath : stream) {
+                try (BufferedReader reader = Files.newBufferedReader(filePath)) {
+                    String line;
+                    while ((line = reader.readLine()) != null) {
+                        if (line.trim().isEmpty() || !line.contains(".")) {
+                            continue;
+                        }
+                        String question = line.substring(line.indexOf(".") + 1).trim();
+                        questions.add(question);
+                    }
+                }
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+        return questions;
+    }
 }

src/services/LoginSystem.java

@@ -1,62 +1,48 @@
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Scanner;
-
-public class LoginSystem {
-    private Map<String, User> users;
-
-    public LoginSystem() {
-        initializeUsers();
-    }
-
-    private void initializeUsers() {
-        users = new HashMap<>();
-
-        // 小学账户
-        users.put("张三1", new User("张三1", "123", DifficultyLevel.PRIMARY));
-        users.put("张三2", new User("张三2", "123", DifficultyLevel.PRIMARY));
-        users.put("张三3", new User("张三3", "123", DifficultyLevel.PRIMARY));
-
-        // 初中账户
-        users.put("李四1", new User("李四1", "123", DifficultyLevel.JUNIOR));
-        users.put("李四2", new User("李四2", "123", DifficultyLevel.JUNIOR));
-        users.put("李四3", new User("李四3", "123", DifficultyLevel.JUNIOR));
-
-        // 高中账户
-        users.put("王五1", new User("王五1", "123", DifficultyLevel.SENIOR));
-        users.put("王五2", new User("王五2", "123", DifficultyLevel.SENIOR));
-        users.put("王五3", new User("王五3", "123", DifficultyLevel.SENIOR));
-    }
-
-    public User login(Scanner scanner) {
-        while (true) {
-            System.out.print("请输入用户名和密码（用空格隔开）：");
-            String input = scanner.nextLine().trim();
-            String[] parts = input.split("\\s+");
-
-            if (parts.length != 2) {
-                System.out.println("请输入正确的用户名、密码");
-                continue;
-            }
-
-            String username = parts[0];
-            String password = parts[1];
-
-            User user = users.get(username);
-            if (user != null && user.getPassword().equals(password)) {
-                return user;
-            } else {
-                System.out.println("请输入正确的用户名、密码");
-            }
-        }
-    }
-
-    public DifficultyLevel switchLevel(String levelName) {
-        DifficultyLevel newLevel = DifficultyLevel.fromString(levelName);
-        if (newLevel == null) {
-            System.out.println("请输入小学、初中和高中三个选项中的一个");
-            return null;
-        }
-        return newLevel;
-    }
+package services;
+
+import interfaces.LoginSystemInterface;
+import models.User;
+import models.DifficultyLevel;
+import java.util.HashMap;
+import java.util.Map;
+
+public class LoginSystem implements LoginSystemInterface {
+    private Map<String, User> users;
+
+    public LoginSystem() {
+        initializeUsers();
+    }
+
+    private void initializeUsers() {
+        users = new HashMap<>();
+
+        users.put("张三1", new User("张三1", "123", DifficultyLevel.PRIMARY));
+        users.put("张三2", new User("张三2", "123", DifficultyLevel.PRIMARY));
+        users.put("张三3", new User("张三3", "123", DifficultyLevel.PRIMARY));
+        users.put("李四1", new User("李四1", "123", DifficultyLevel.JUNIOR));
+        users.put("李四2", new User("李四2", "123", DifficultyLevel.JUNIOR));
+        users.put("李四3", new User("李四3", "123", DifficultyLevel.JUNIOR));
+        users.put("王五1", new User("王五1", "123", DifficultyLevel.SENIOR));
+        users.put("王五2", new User("王五2", "123", DifficultyLevel.SENIOR));
+        users.put("王五3", new User("王五3", "123", DifficultyLevel.SENIOR));
+    }
+
+    @Override
+    public User login(String username, String password) {
+        User user = users.get(username);
+        if (user != null && user.getPassword().equals(password)) {
+            return user;
+        }
+        return null;
+    }
+
+    @Override
+    public DifficultyLevel switchLevel(String levelName) {
+        DifficultyLevel newLevel = DifficultyLevel.fromString(levelName);
+        if (newLevel == null) {
+            System.out.println("请输入小学、初中和高中三个选项中的一个");
+            return null;
+        }
+        return newLevel;
+    }
 }

src/services/MathQuestion.java

@@ -0,0 +1,148 @@
+package services;
+
+import interfaces.QuestionInterface;
+import models.DifficultyLevel;
+import java.util.Random;
+
+public class MathQuestion implements QuestionInterface {
+    private String questionText;
+    private DifficultyLevel difficulty;
+    private Random random;
+    private boolean isValid;
+
+    public MathQuestion(DifficultyLevel difficulty) {
+        this.difficulty = difficulty;
+        this.random = new Random();
+        this.questionText = generateQuestion();
+        this.isValid = validateQuestion();
+    }
+
+    @Override
+    public String generateQuestion() {
+        StringBuilder question = new StringBuilder();
+
+        switch (difficulty) {
+            case PRIMARY:
+                question.append(generatePrimaryQuestion());
+                break;
+            case JUNIOR:
+                question.append(generateJuniorQuestion());
+                break;
+            case SENIOR:
+                question.append(generateSeniorQuestion());
+                break;
+        }
+
+        question.append(" = ");
+        return question.toString();
+    }
+
+    @Override
+    public boolean isValid() {
+        return isValid;
+    }
+
+    private boolean validateQuestion() {
+        if (questionText == null || questionText.trim().isEmpty()) {
+            return false;
+        }
+
+        // 小学题目必须至少有2个操作数
+        if (difficulty == DifficultyLevel.PRIMARY) {
+            String expr = questionText.replace(" = ", "");
+            // 统计操作符数量来判断操作数数量
+            int operatorCount = countOperators(expr);
+            return operatorCount >= 1; // 1个操作符表示2个操作数
+        }
+
+        return true;
+    }
+
+    private int countOperators(String expression) {
+        int count = 0;
+        for (char c : expression.toCharArray()) {
+            if (c == '+' || c == '-' || c == '*' || c == '/') {
+                count++;
+            }
+        }
+        return count;
+    }
+
+    @Override
+    public String getQuestionText() {
+        return questionText;
+    }
+
+    @Override
+    public DifficultyLevel getDifficulty() {
+        return difficulty;
+    }
+
+    private String generatePrimaryQuestion() {
+        // 小学题目：确保至少有2个操作数（2-5个）
+        int operandCount = random.nextInt(4) + 2; // 2-5个操作数
+        String[] operators = {"+", "-", "*", "/"};
+        StringBuilder question = new StringBuilder();
+
+        for (int i = 0; i < operandCount; i++) {
+            if (i > 0) {
+                question.append(" ").append(operators[random.nextInt(operators.length)]).append(" ");
+            }
+            question.append(random.nextInt(100) + 1);
+
+            // 随机添加括号（小学难度）
+            if (operandCount > 2 && random.nextDouble() < 0.3) {
+                question.insert(0, "(").append(")");
+            }
+        }
+        return question.toString();
+    }
+
+    private String generateJuniorQuestion() {
+        // 初中题目：可以有1个操作数（涉及平方、开根号）
+        int choice = random.nextInt(3);
+        switch (choice) {
+            case 0:
+                // 单个操作数：开根号
+                return "√" + (random.nextInt(100) + 1);
+            case 1:
+                // 单个操作数：平方
+                return "(" + (random.nextInt(10) + 1) + ")²";
+            case 2:
+                // 多个操作数：基础运算 + 平方/开根号
+                String baseQuestion = generatePrimaryQuestion();
+                if (random.nextBoolean()) {
+                    return "√" + (random.nextInt(100) + 1) + " + " + baseQuestion;
+                } else {
+                    return "(" + (random.nextInt(10) + 1) + ")² + " + baseQuestion;
+                }
+            default:
+                return generatePrimaryQuestion();
+        }
+    }
+
+    private String generateSeniorQuestion() {
+        // 高中题目：可以有1个操作数（涉及三角函数）
+        int choice = random.nextInt(3);
+        String[] trigFunctions = {"sin", "cos", "tan"};
+
+        switch (choice) {
+            case 0:
+                // 单个操作数：三角函数
+                return trigFunctions[random.nextInt(trigFunctions.length)] +
+                        "(" + (random.nextInt(90) + 1) + "°)";
+            case 1:
+                // 三角函数 + 基础运算
+                String baseQuestion = generatePrimaryQuestion();
+                return trigFunctions[random.nextInt(trigFunctions.length)] +
+                        "(" + (random.nextInt(90) + 1) + "°) + " + baseQuestion;
+            case 2:
+                // 复杂组合：三角函数 + 平方/开根号 + 基础运算
+                String complexBase = generateJuniorQuestion();
+                return trigFunctions[random.nextInt(trigFunctions.length)] +
+                        "(" + (random.nextInt(90) + 1) + "°) + " + complexBase;
+            default:
+                return generatePrimaryQuestion();
+        }
+    }
+}

src/services/QuestionGenerator.java

@@ -0,0 +1,43 @@
+package services;
+
+import interfaces.QuestionInterface;
+import models.DifficultyLevel;
+import java.util.HashSet;
+import java.util.Random;
+import java.util.Set;
+
+public class QuestionGenerator {
+    private Random random;
+    private FileManager fileManager;
+
+    public QuestionGenerator() {
+        random = new Random();
+        fileManager = new FileManager();
+    }
+
+    public String[] generateQuestions(DifficultyLevel level, int count, String username) {
+        Set<String> existingQuestions = fileManager.loadExistingQuestions(username);
+        Set<String> newQuestions = new HashSet<>();
+        String[] questions = new String[count];
+
+        for (int i = 0; i < count; i++) {
+            QuestionInterface question;
+            int attempts = 0;
+
+            do {
+                question = new MathQuestion(level);
+                attempts++;
+                if (attempts > 100) {
+                    return null;
+                }
+            } while (existingQuestions.contains(question.getQuestionText()) ||
+                    newQuestions.contains(question.getQuestionText()) ||
+                    !question.isValid());
+
+            newQuestions.add(question.getQuestionText());
+            questions[i] = (i + 1) + ". " + question.getQuestionText();
+        }
+
+        return questions;
+    }
+}