diff --git a/.idea/misc.xml b/.idea/misc.xml
index 12ee456..ee1d9a3 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_22" project-jdk-name="23" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" project-jdk-name="23" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..c8397c9
--- /dev/null
+++ b/.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>
\ No newline at end of file
diff --git a/src/com/mathlearning/controller/QuestionController.java b/src/com/mathlearning/controller/QuestionController.java
index e793a9f..228fdad 100644
--- a/src/com/mathlearning/controller/QuestionController.java
+++ b/src/com/mathlearning/controller/QuestionController.java
@@ -1,8 +1,8 @@
 package com.mathlearning.controller;
 
 import com.mathlearning.model.Question;
+import com.mathlearning.model.ConcreteQuestionGenerator;
 import com.mathlearning.model.QuestionGenerator;
-
 import java.util.List;
 
 public class QuestionController {
@@ -10,68 +10,131 @@ public class QuestionController {
   private List<Question> currentQuestions;
   private int currentQuestionIndex;
   private int score;
-  private int[] userAnswers;
 
   public QuestionController() {
-    this.questionGenerator = new QuestionGenerator();
+    this.questionGenerator = new ConcreteQuestionGenerator();
+    this.currentQuestionIndex = 0;
+    this.score = 0;
+  }
+
+  // 原有的生成问题方法
+  public List<Question> generateQuestions(String level, int count) {
+    return questionGenerator.generateQuestions(level, count);
   }
 
+  // 原有的显示问题方法
+  public void displayQuestions(String level, int count) {
+    List<Question> questions = generateQuestions(level, count);
+    System.out.println(level + "题目:");
+    for (int i = 0; i < questions.size(); i++) {
+      Question q = questions.get(i);
+      System.out.println((i + 1) + ". " + q.getQuestionText());
+      String[] options = q.getOptions();
+      for (int j = 0; j < options.length; j++) {
+        System.out.println("   " + (char)('A' + j) + ". " + options[j]);
+      }
+      System.out.println("   正确答案: " + (char)('A' + q.getCorrectIndex()));
+      System.out.println();
+    }
+  }
+
+  // 新增加的测验管理方法
+
+  // 开始新测验
   public void startNewQuiz(String level, int questionCount) {
     this.currentQuestions = questionGenerator.generateQuestions(level, questionCount);
     this.currentQuestionIndex = 0;
     this.score = 0;
-    this.userAnswers = new int[questionCount];
-    // Initialize with -1 (no answer)
-    for (int i = 0; i < userAnswers.length; i++) {
-      userAnswers[i] = -1;
-    }
   }
 
-  /*
+  // 获取当前问题列表 - 新增的方法
+  public List<Question> getCurrentQuestions() {
+    return currentQuestions;
+  }
+
+  // 获取当前问题
   public Question getCurrentQuestion() {
-    if (currentQuestions == null || currentQuestionIndex >= currentQuestions.size()) {
+    if (currentQuestions == null || currentQuestions.isEmpty()) {
       return null;
     }
     return currentQuestions.get(currentQuestionIndex);
   }
 
-  public void submitAnswer(int answerIndex) {
-    if (currentQuestionIndex < userAnswers.length) {
-      userAnswers[currentQuestionIndex] = answerIndex;
+  // 获取当前问题索引
+  public int getCurrentQuestionIndex() {
+    return currentQuestionIndex;
+  }
+
+  // 获取问题总数
+  public int getTotalQuestions() {
+    return currentQuestions != null ? currentQuestions.size() : 0;
+  }
+
+  // 提交答案并检查是否正确
+  public boolean submitAnswer(int selectedOption) {
+    if (currentQuestions == null || currentQuestionIndex >= currentQuestions.size()) {
+      return false;
     }
 
-    if (answerIndex != -1 && currentQuestions.get(currentQuestionIndex).isCorrect(answerIndex)) {
+    Question currentQuestion = currentQuestions.get(currentQuestionIndex);
+    boolean isCorrect = (selectedOption == currentQuestion.getCorrectIndex());
+
+    if (isCorrect) {
       score++;
     }
 
-    currentQuestionIndex++;
+    return isCorrect;
   }
 
-  public boolean hasNextQuestion() {
-    return currentQuestions != null && currentQuestionIndex < currentQuestions.size();
+  // 移动到下一个问题
+  public boolean nextQuestion() {
+    if (currentQuestions == null || currentQuestionIndex >= currentQuestions.size() - 1) {
+      return false;
+    }
+    currentQuestionIndex++;
+    return true;
   }
 
-  public int getCurrentQuestionNumber() {
-    return currentQuestionIndex + 1;
-  }
-  */
-  public int getTotalQuestions() {
-    return currentQuestions != null ? currentQuestions.size() : 0;
+  // 移动到上一个问题
+  public boolean previousQuestion() {
+    if (currentQuestions == null || currentQuestionIndex <= 0) {
+      return false;
+    }
+    currentQuestionIndex--;
+    return true;
   }
 
+  // 获取当前分数
   public int getScore() {
     return score;
   }
 
-  public double getPercentage() {
-    return getTotalQuestions() > 0 ? (double) score / getTotalQuestions() * 100 : 0;
+  // 检查是否还有更多问题
+  public boolean hasMoreQuestions() {
+    return currentQuestions != null && currentQuestionIndex < currentQuestions.size() - 1;
   }
 
-  public int[] getUserAnswers() {
-    return userAnswers;
+  // 检查测验是否完成
+  public boolean isQuizCompleted() {
+    return currentQuestions != null && currentQuestionIndex >= currentQuestions.size() - 1;
   }
 
-  public List<Question> getCurrentQuestions() {
+  // 获取所有问题（用于显示结果等）
+  public List<Question> getAllQuestions() {
     return currentQuestions;
   }
-}
+
+  // 重置测验状态
+  public void resetQuiz() {
+    this.currentQuestions = null;
+    this.currentQuestionIndex = 0;
+    this.score = 0;
+  }
+
+  // 直接设置当前问题索引（如果需要）
+  public void setCurrentQuestionIndex(int index) {
+    if (currentQuestions != null && index >= 0 && index < currentQuestions.size()) {
+      this.currentQuestionIndex = index;
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/AbstractQuestionGenerator.java b/src/com/mathlearning/model/AbstractQuestionGenerator.java
new file mode 100644
index 0000000..1b9513f
--- /dev/null
+++ b/src/com/mathlearning/model/AbstractQuestionGenerator.java
@@ -0,0 +1,41 @@
+package com.mathlearning.model;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public abstract class AbstractQuestionGenerator implements QuestionGenerator {
+
+    @Override
+    public List<Question> generateQuestions(String level, int count) {
+        List<Question> questions = new ArrayList<>();
+        Set<String> questionTexts = new HashSet<>();
+
+        for (int i = 0; i < count; i++) {
+            Question question = generateUniqueQuestion(level, i, questionTexts);
+            if (question != null) {
+                questions.add(question);
+            }
+        }
+
+        return questions;
+    }
+
+    private Question generateUniqueQuestion(String level, int index, Set<String> questionTexts) {
+        Question question;
+        int attempt = 0;
+        do {
+            question = generateQuestion(level, index);
+            attempt++;
+        } while (question != null && questionTexts.contains(question.getQuestionText()) && attempt < 10);
+
+        if (question != null) {
+            questionTexts.add(question.getQuestionText());
+        }
+
+        return question;
+    }
+
+    protected abstract Question generateQuestion(String level, int index);
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/BaseQuestionGenerator.java b/src/com/mathlearning/model/BaseQuestionGenerator.java
new file mode 100644
index 0000000..2a82651
--- /dev/null
+++ b/src/com/mathlearning/model/BaseQuestionGenerator.java
@@ -0,0 +1,192 @@
+package com.mathlearning.model;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Random;
+import java.util.Set;
+
+public abstract class BaseQuestionGenerator {
+    protected Random random = new Random();
+
+    public abstract Question generateQuestion(int index);
+
+    protected void generateOperands(int[] operands, int min, int max) {
+        for (int i = 0; i < operands.length; i++) {
+            operands[i] = random.nextInt(max - min + 1) + min;
+        }
+    }
+
+    protected void generateOperations(int[] operations, int operationTypes) {
+        for (int i = 0; i < operations.length; i++) {
+            operations[i] = random.nextInt(operationTypes);
+        }
+    }
+
+    protected void appendOperator(StringBuilder sb, int operation) {
+        switch (operation) {
+            case 0: sb.append(" + "); break;
+            case 1: sb.append(" - "); break;
+            case 2: sb.append(" × "); break;
+            case 3: sb.append(" ÷ "); break;
+        }
+    }
+
+    protected boolean isValidAnswer(double answer) {
+        return !(answer < 0 || Double.isNaN(answer) || Double.isInfinite(answer));
+    }
+
+    // 修改：使用double进行精确计算，只在最后保留小数
+    protected double calculateExpression(double[] values, int[] operations) {
+        List<Double> numbers = new ArrayList<>();
+        List<Integer> ops = new ArrayList<>();
+
+        for (double value : values) numbers.add(value);
+        for (int operation : operations) ops.add(operation);
+
+        processMultiplicationAndDivision(numbers, ops);
+        return processAdditionAndSubtraction(numbers, ops);
+    }
+
+    protected double calculateWithoutParentheses(int[] operands, int[] operations) {
+        double[] doubleOperands = new double[operands.length];
+        for (int i = 0; i < operands.length; i++) {
+            doubleOperands[i] = operands[i];
+        }
+        return calculateExpression(doubleOperands, operations);
+    }
+
+    protected double calculateWithoutParentheses(List<Integer> numbers, List<Integer> ops) {
+        double[] doubleNumbers = new double[numbers.size()];
+        for (int i = 0; i < numbers.size(); i++) {
+            doubleNumbers[i] = numbers.get(i);
+        }
+
+        int[] intOps = new int[ops.size()];
+        for (int i = 0; i < ops.size(); i++) {
+            intOps[i] = ops.get(i);
+        }
+
+        return calculateExpression(doubleNumbers, intOps);
+    }
+
+    private void processMultiplicationAndDivision(List<Double> numbers, List<Integer> ops) {
+        for (int i = 0; i < ops.size(); i++) {
+            int op = ops.get(i);
+            if (op == 2 || op == 3) {
+                double left = numbers.get(i);
+                double right = numbers.get(i + 1);
+                double result = performOperation(left, right, op);
+
+                numbers.set(i, result);
+                numbers.remove(i + 1);
+                ops.remove(i);
+                i--;
+            }
+        }
+    }
+
+    private double processAdditionAndSubtraction(List<Double> numbers, List<Integer> ops) {
+        double result = numbers.get(0);
+
+        for (int i = 0; i < ops.size(); i++) {
+            int op = ops.get(i);
+            double nextNum = numbers.get(i + 1);
+            result = performOperation(result, nextNum, op);
+        }
+
+        // 修改：只在最后一步进行四舍五入保留2位小数
+        return Math.round(result * 100) / 100.0;
+    }
+
+    private double performOperation(double left, double right, int operation) {
+        switch (operation) {
+            case 0: return left + right;
+            case 1: return left - right;
+            case 2: return left * right;
+            case 3:
+                if (right == 0) return Double.NaN;
+                // 修改：直接进行除法，不在这里保留小数
+                return left / right;
+            default: return left;
+        }
+    }
+
+    protected Question generateOptions(String questionText, double answer, String level) {
+        String[] options = new String[4];
+        Set<String> usedValues = new HashSet<>();
+
+        // 修改：判断是否为整数的逻辑
+        boolean isIntegerAnswer = Math.abs(answer - Math.round(answer)) < 1e-10;
+        String correctAnswer = formatAnswer(answer, isIntegerAnswer);
+
+        options[0] = correctAnswer;
+        usedValues.add(correctAnswer);
+
+        generateWrongOptions(options, usedValues, answer, isIntegerAnswer);
+        shuffleArray(options);
+
+        int correctIndex = findCorrectIndex(options, correctAnswer);
+        return new Question(questionText, options, correctIndex, level);
+    }
+
+    private void generateWrongOptions(String[] options, Set<String> usedValues,
+                                      double answer, boolean isIntegerAnswer) {
+        for (int i = 1; i < 4; i++) {
+            String wrongAnswer;
+            int attempts = 0;
+
+            do {
+                double wrongValue = generateWrongValue(answer, isIntegerAnswer);
+                wrongAnswer = formatAnswer(wrongValue,
+                        Math.abs(wrongValue - Math.round(wrongValue)) < 1e-10);
+                attempts++;
+            } while (usedValues.contains(wrongAnswer) && attempts < 20);
+
+            options[i] = wrongAnswer;
+            usedValues.add(wrongAnswer);
+        }
+    }
+
+    private double generateWrongValue(double answer, boolean isIntegerAnswer) {
+        double offset = (random.nextDouble() * 5) + 1;
+
+        if (isIntegerAnswer) {
+            int intAnswer = (int) Math.round(answer);
+            int intOffset = random.nextInt(10) + 1;
+            double wrongValue = random.nextBoolean() ?
+                    intAnswer + intOffset : Math.max(1, intAnswer - intOffset);
+            return wrongValue;
+        } else {
+            double wrongValue = random.nextBoolean() ? answer + offset : answer - offset;
+            // 修改：错误选项也保留2位小数
+            return Math.round(wrongValue * 100) / 100.0;
+        }
+    }
+
+    // 修改：格式化答案，只在最后一步处理小数位数
+    private String formatAnswer(double answer, boolean isInteger) {
+        if (isInteger) {
+            return String.valueOf((int) Math.round(answer));
+        } else {
+            // 确保显示2位小数，即使末尾是0
+            return String.format("%.2f", answer);
+        }
+    }
+
+    private void shuffleArray(String[] array) {
+        for (int i = array.length - 1; i > 0; i--) {
+            int j = random.nextInt(i + 1);
+            String temp = array[i];
+            array[i] = array[j];
+            array[j] = temp;
+        }
+    }
+
+    private int findCorrectIndex(String[] options, String correctAnswer) {
+        for (int i = 0; i < options.length; i++) {
+            if (options[i].equals(correctAnswer)) return i;
+        }
+        return 0;
+    }
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/ConcreteQuestionGenerator.java b/src/com/mathlearning/model/ConcreteQuestionGenerator.java
new file mode 100644
index 0000000..446d689
--- /dev/null
+++ b/src/com/mathlearning/model/ConcreteQuestionGenerator.java
@@ -0,0 +1,21 @@
+package com.mathlearning.model;
+
+public class ConcreteQuestionGenerator extends AbstractQuestionGenerator {
+    private PrimaryQuestionGenerator primaryGenerator = new PrimaryQuestionGenerator();
+    private MiddleSchoolQuestionGenerator middleSchoolGenerator = new MiddleSchoolQuestionGenerator();
+    private HighSchoolQuestionGenerator highSchoolGenerator = new HighSchoolQuestionGenerator();
+
+    @Override
+    protected Question generateQuestion(String level, int index) {
+        switch (level) {
+            case "小学":
+                return primaryGenerator.generateQuestion(index);
+            case "初中":
+                return middleSchoolGenerator.generateQuestion(index);
+            case "高中":
+                return highSchoolGenerator.generateQuestion(index);
+            default:
+                return primaryGenerator.generateQuestion(index);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/HighSchoolQuestionGenerator.java b/src/com/mathlearning/model/HighSchoolQuestionGenerator.java
new file mode 100644
index 0000000..bde9d3c
--- /dev/null
+++ b/src/com/mathlearning/model/HighSchoolQuestionGenerator.java
@@ -0,0 +1,112 @@
+package com.mathlearning.model;
+
+public class HighSchoolQuestionGenerator extends BaseQuestionGenerator {
+    private static final int[] SPECIAL_ANGLES = {0, 15, 30, 45, 60, 75, 90};
+
+    @Override
+    public Question generateQuestion(int index) {
+        int operandCount = random.nextInt(5) + 1;
+        int[] operands = new int[operandCount];
+        int[] operations = new int[Math.max(0, operandCount - 1)];
+        boolean[] hasTrigOp = new boolean[operandCount];
+        int[] trigFunctions = new int[operandCount];
+
+        ensureTrigOperation(hasTrigOp, trigFunctions, operandCount);
+
+        String questionText;
+        double answer;
+
+        do {
+            generateOperandsWithTrig(operands, hasTrigOp);
+            generateOperations(operations, 4);
+
+            questionText = buildQuestionText(operands, operations, hasTrigOp, trigFunctions);
+            answer = calculateAnswer(operands, operations, hasTrigOp, trigFunctions);
+
+        } while (!isValidAnswer(answer) || Math.abs(answer) > 10000);
+
+        return generateOptions(questionText, answer, "高中");
+    }
+
+    private void ensureTrigOperation(boolean[] hasTrigOp, int[] trigFunctions, int operandCount) {
+        boolean hasTrigOperation = false;
+
+        for (int i = 0; i < operandCount; i++) {
+            hasTrigOp[i] = random.nextDouble() < 0.6;
+            if (hasTrigOp[i]) hasTrigOperation = true;
+        }
+
+        if (!hasTrigOperation && operandCount > 0) {
+            int idx = random.nextInt(operandCount);
+            hasTrigOp[idx] = true;
+            trigFunctions[idx] = random.nextInt(3);
+        }
+    }
+
+    private void generateOperandsWithTrig(int[] operands, boolean[] hasTrigOp) {
+        for (int i = 0; i < operands.length; i++) {
+            operands[i] = hasTrigOp[i] ?
+                    SPECIAL_ANGLES[random.nextInt(SPECIAL_ANGLES.length)] :
+                    random.nextInt(100) + 1;
+        }
+    }
+
+    private String buildQuestionText(int[] operands, int[] operations,
+                                     boolean[] hasTrigOp, int[] trigFunctions) {
+        StringBuilder sb = new StringBuilder();
+
+        for (int i = 0; i < operands.length; i++) {
+            if (i > 0) appendOperator(sb, operations[i - 1]);
+
+            if (hasTrigOp[i]) {
+                appendTrigFunction(sb, operands[i], trigFunctions[i]);
+            } else {
+                sb.append(operands[i]);
+            }
+        }
+
+        sb.append(" = ?");
+        return sb.toString();
+    }
+
+    private void appendTrigFunction(StringBuilder sb, int operand, int trigFunction) {
+        switch (trigFunction) {
+            case 0: sb.append("sin(").append(operand).append("°)"); break;
+            case 1: sb.append("cos(").append(operand).append("°)"); break;
+            case 2: sb.append("tan(").append(operand).append("°)"); break;
+        }
+    }
+
+    private double calculateAnswer(int[] operands, int[] operations,
+                                   boolean[] hasTrigOp, int[] trigFunctions) {
+        double[] processedValues = processTrigOperations(operands, hasTrigOp, trigFunctions);
+        return calculateExpression(processedValues, operations);
+    }
+
+    private double[] processTrigOperations(int[] operands, boolean[] hasTrigOp, int[] trigFunctions) {
+        double[] processedValues = new double[operands.length];
+
+        for (int i = 0; i < operands.length; i++) {
+            if (hasTrigOp[i]) {
+                processedValues[i] = calculateTrigFunction(operands[i], trigFunctions[i]);
+            } else {
+                processedValues[i] = operands[i];
+            }
+        }
+
+        return processedValues;
+    }
+
+    private double calculateTrigFunction(int angle, int trigFunction) {
+        double radians = Math.toRadians(angle);
+
+        switch (trigFunction) {
+            case 0: return Math.sin(radians);
+            case 1: return Math.cos(radians);
+            case 2:
+                if (angle % 180 == 90 && angle % 360 != 270) return Double.NaN;
+                return Math.tan(radians);
+            default: return 0;
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/MiddleSchoolQuestionGenerator.java b/src/com/mathlearning/model/MiddleSchoolQuestionGenerator.java
new file mode 100644
index 0000000..c1b1537
--- /dev/null
+++ b/src/com/mathlearning/model/MiddleSchoolQuestionGenerator.java
@@ -0,0 +1,91 @@
+package com.mathlearning.model;
+
+public class MiddleSchoolQuestionGenerator extends BaseQuestionGenerator {
+
+    @Override
+    public Question generateQuestion(int index) {
+        int operandCount = random.nextInt(5) + 1;
+        int[] operands = new int[operandCount];
+        int[] operations = new int[Math.max(0, operandCount - 1)];
+        boolean[] hasSpecialOp = new boolean[operandCount];
+        int[] specialOpTypes = new int[operandCount];
+
+        ensureSpecialOperation(hasSpecialOp, specialOpTypes, operandCount);
+
+        String questionText;
+        double answer;
+
+        do {
+            generateOperands(operands, 1, 100);
+            generateOperations(operations, 4);
+
+            questionText = buildQuestionText(operands, operations, hasSpecialOp, specialOpTypes);
+            answer = calculateAnswer(operands, operations, hasSpecialOp, specialOpTypes);
+
+        } while (!isValidAnswer(answer) || Math.abs(answer) > 10000);
+
+        return generateOptions(questionText, answer, "初中");
+    }
+
+    private void ensureSpecialOperation(boolean[] hasSpecialOp, int[] specialOpTypes, int operandCount) {
+        boolean hasSpecialOperation = false;
+
+        for (int i = 0; i < operandCount; i++) {
+            hasSpecialOp[i] = random.nextDouble() < 0.6;
+            if (hasSpecialOp[i]) hasSpecialOperation = true;
+        }
+
+        if (!hasSpecialOperation && operandCount > 0) {
+            int idx = random.nextInt(operandCount);
+            hasSpecialOp[idx] = true;
+            specialOpTypes[idx] = random.nextInt(2);
+        }
+    }
+
+    private String buildQuestionText(int[] operands, int[] operations,
+                                     boolean[] hasSpecialOp, int[] specialOpTypes) {
+        StringBuilder sb = new StringBuilder();
+
+        for (int i = 0; i < operands.length; i++) {
+            if (i > 0) appendOperator(sb, operations[i - 1]);
+
+            if (hasSpecialOp[i]) {
+                appendSpecialOperation(sb, operands[i], specialOpTypes[i]);
+            } else {
+                sb.append(operands[i]);
+            }
+        }
+
+        sb.append(" = ?");
+        return sb.toString();
+    }
+
+    private void appendSpecialOperation(StringBuilder sb, int operand, int opType) {
+        if (opType == 0) {
+            sb.append(operand).append("²");
+        } else {
+            sb.append("√").append(operand);
+        }
+    }
+
+    private double calculateAnswer(int[] operands, int[] operations,
+                                   boolean[] hasSpecialOp, int[] specialOpTypes) {
+        double[] processedValues = processSpecialOperations(operands, hasSpecialOp, specialOpTypes);
+        return calculateExpression(processedValues, operations);
+    }
+
+    private double[] processSpecialOperations(int[] operands, boolean[] hasSpecialOp, int[] specialOpTypes) {
+        double[] processedValues = new double[operands.length];
+
+        for (int i = 0; i < operands.length; i++) {
+            if (hasSpecialOp[i]) {
+                processedValues[i] = (specialOpTypes[i] == 0) ?
+                        operands[i] * operands[i] : Math.sqrt(operands[i]);
+            } else {
+                processedValues[i] = operands[i];
+            }
+        }
+
+        return processedValues;
+    }
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/PrimaryQuestionGenerator.java b/src/com/mathlearning/model/PrimaryQuestionGenerator.java
new file mode 100644
index 0000000..675322f
--- /dev/null
+++ b/src/com/mathlearning/model/PrimaryQuestionGenerator.java
@@ -0,0 +1,143 @@
+package com.mathlearning.model;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class PrimaryQuestionGenerator extends BaseQuestionGenerator {
+
+    @Override
+    public Question generateQuestion(int index) {
+        int operandCount = random.nextInt(4) + 2;
+        int[] operands = new int[operandCount];
+        int[] operations = new int[operandCount - 1];
+
+        String questionText;
+        double answer;
+
+        do {
+            generateOperands(operands, 1, 100);
+            generateOperations(operations, 4);
+
+            boolean useParentheses = random.nextDouble() < 0.3 && operandCount >= 3;
+            int[] parenthesesPositions = findParenthesesPositions(operations, useParentheses);
+
+            questionText = buildQuestionText(operands, operations,
+                    parenthesesPositions[0], parenthesesPositions[1]);
+            answer = calculateAnswer(operands, operations,
+                    parenthesesPositions[0], parenthesesPositions[1]);
+
+        } while (!isValidAnswer(answer));
+
+        return generateOptions(questionText, answer, "小学");
+    }
+
+    private int[] findParenthesesPositions(int[] operations, boolean useParentheses) {
+        int parenStart = -1;
+        int parenEnd = -1;
+
+        if (useParentheses) {
+            parenStart = findSuitableParenthesesPosition(operations);
+            if (parenStart != -1) {
+                parenEnd = parenStart + 1;
+                if (parenEnd < operations.length && random.nextBoolean()) {
+                    parenEnd++;
+                }
+            }
+        }
+
+        return new int[]{parenStart, parenEnd};
+    }
+
+    private int findSuitableParenthesesPosition(int[] operations) {
+        List<Integer> suitablePositions = new ArrayList<>();
+
+        for (int i = 0; i < operations.length; i++) {
+            if ((operations[i] == 0 || operations[i] == 1) && i > 0) {
+                suitablePositions.add(i);
+            }
+        }
+
+        if (suitablePositions.isEmpty()) {
+            return operations.length > 1 ? random.nextInt(operations.length - 1) : -1;
+        }
+
+        return suitablePositions.get(random.nextInt(suitablePositions.size()));
+    }
+
+    private String buildQuestionText(int[] operands, int[] operations, int parenStart, int parenEnd) {
+        StringBuilder sb = new StringBuilder();
+
+        for (int i = 0; i < operands.length; i++) {
+            if (i == parenStart) sb.append("(");
+            sb.append(operands[i]);
+            if (i == parenEnd) sb.append(")");
+            if (i < operations.length) appendOperator(sb, operations[i]);
+        }
+
+        sb.append(" = ?");
+        return sb.toString();
+    }
+
+    private double calculateAnswer(int[] operands, int[] operations, int parenStart, int parenEnd) {
+        if (parenStart == -1 || parenEnd == -1) {
+            return calculateWithoutParentheses(operands, operations);
+        }
+
+        return calculateWithParentheses(operands, operations, parenStart, parenEnd);
+    }
+
+    private double calculateWithParentheses(int[] operands, int[] operations, int parenStart, int parenEnd) {
+        // 修改：使用Double列表
+        List<Double> numbers = new ArrayList<>();
+        List<Integer> ops = new ArrayList<>();
+
+        for (int operand : operands) numbers.add((double) operand);
+        for (int operation : operations) ops.add(operation);
+
+        double parenthesesResult = calculateParenthesesContent(numbers, ops, parenStart, parenEnd);
+
+        if (!isValidAnswer(parenthesesResult)) return -1;
+
+        replaceWithParenthesesResult(numbers, ops, parenStart, parenEnd, parenthesesResult);
+        // 修改：调用新的方法名
+        return calculateDoubleList(numbers, ops);
+    }
+
+    private double calculateParenthesesContent(List<Double> numbers, List<Integer> ops, int start, int end) {
+        List<Double> parenNumbers = new ArrayList<>();
+        List<Integer> parenOps = new ArrayList<>();
+
+        for (int i = start; i <= end; i++) parenNumbers.add(numbers.get(i));
+        for (int i = start; i < end; i++) parenOps.add(ops.get(i));
+
+        // 修改：调用新的方法名
+        return calculateDoubleList(parenNumbers, parenOps);
+    }
+
+    private void replaceWithParenthesesResult(List<Double> numbers, List<Integer> ops,
+                                              int start, int end, double result) {
+        int numCountToRemove = end - start + 1;
+        int opCountToRemove = end - start;
+
+        for (int i = 0; i < numCountToRemove; i++) numbers.remove(start);
+        for (int i = 0; i < opCountToRemove; i++) ops.remove(start);
+
+        // 修改：直接添加double结果，不转换为int
+        numbers.add(start, result);
+    }
+
+    // 修改：重命名方法，避免与父类冲突
+    private double calculateDoubleList(List<Double> numbers, List<Integer> ops) {
+        double[] doubleNumbers = new double[numbers.size()];
+        for (int i = 0; i < numbers.size(); i++) {
+            doubleNumbers[i] = numbers.get(i);
+        }
+
+        int[] intOps = new int[ops.size()];
+        for (int i = 0; i < ops.size(); i++) {
+            intOps[i] = ops.get(i);
+        }
+
+        return calculateExpression(doubleNumbers, intOps);
+    }
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/Question.java b/src/com/mathlearning/model/Question.java
index 3094ba2..592904a 100644
--- a/src/com/mathlearning/model/Question.java
+++ b/src/com/mathlearning/model/Question.java
@@ -3,34 +3,45 @@ package com.mathlearning.model;
 public class Question {
   private String questionText;
   private String[] options;
-  private int correctAnswerIndex;
+  private int correctIndex;
   private String level;
 
-  public Question(String questionText, String[] options, int correctAnswerIndex, String level) {
+  public Question(String questionText, String[] options, int correctIndex, String level) {
     this.questionText = questionText;
     this.options = options;
-    this.correctAnswerIndex = correctAnswerIndex;
+    this.correctIndex = correctIndex;
     this.level = level;
   }
 
-  // Getters
   public String getQuestionText() {
     return questionText;
   }
 
+  public void setQuestionText(String questionText) {
+    this.questionText = questionText;
+  }
+
   public String[] getOptions() {
     return options;
   }
 
-  public int getCorrectAnswerIndex() {
-    return correctAnswerIndex;
+  public void setOptions(String[] options) {
+    this.options = options;
+  }
+
+  public int getCorrectIndex() {
+    return correctIndex;
+  }
+
+  public void setCorrectIndex(int correctIndex) {
+    this.correctIndex = correctIndex;
   }
 
   public String getLevel() {
     return level;
   }
 
-  public boolean isCorrect(int selectedIndex) {
-    return selectedIndex == correctAnswerIndex;
+  public void setLevel(String level) {
+    this.level = level;
   }
-}
+}
\ No newline at end of file
diff --git a/src/com/mathlearning/model/QuestionGenerator.java b/src/com/mathlearning/model/QuestionGenerator.java
index 871427b..2b43c4f 100644
--- a/src/com/mathlearning/model/QuestionGenerator.java
+++ b/src/com/mathlearning/model/QuestionGenerator.java
@@ -1,486 +1,7 @@
 package com.mathlearning.model;
 
-import java.util.ArrayList;
-import java.util.HashSet;
 import java.util.List;
-import java.util.Random;
-import java.util.Set;
 
-public class QuestionGenerator {
-  private Random random = new Random();
-
-  public List<Question> generateQuestions(String level, int count) {
-    List<Question> questions = new ArrayList<>();
-    Set<String> questionTexts = new HashSet<>();
-
-    for (int i = 0; i < count; i++) {
-      Question question;
-      int attempt = 0;
-      do {
-        question = generateQuestion(level, i);
-        attempt++;
-      } while (questionTexts.contains(question.getQuestionText()) && attempt < 10);
-
-      if (question != null) {
-        questionTexts.add(question.getQuestionText());
-        questions.add(question);
-      }
-    }
-
-    return questions;
-  }
-
-  private Question generateQuestion(String level, int index) {
-    switch (level) {
-      case "小学":
-        return generatePrimaryQuestion(index);
-      case "初中":
-        return generateMiddleSchoolQuestion(index);
-      case "高中":
-        return generateHighSchoolQuestion(index);
-      default:
-        return generatePrimaryQuestion(index);
-    }
-  }
-
-  private Question generatePrimaryQuestion(int index) {
-    int operandCount = random.nextInt(4) + 2;
-    List<Integer> operands = new ArrayList<>();
-    List<Character> operators = new ArrayList<>();
-
-    // 生成操作数和运算符，确保结果非负
-    generateSafePrimaryExpression(operands, operators, operandCount);
-
-    String questionText;
-    int result;
-    int attempts = 0;
-
-    do {
-      boolean useParentheses = random.nextBoolean() && operandCount >= 3;
-      if (useParentheses) {
-        int parenPos = random.nextInt(operandCount - 1);
-        questionText = buildParenthesesExpression(operands, operators, parenPos);
-        result = evaluateWithParentheses(operands, operators, parenPos);
-      } else {
-        questionText = buildSimpleExpression(operands, operators);
-        result = evaluateSequential(operands, operators);
-      }
-
-      attempts++;
-      if (result < 0) {
-        // 重新生成安全的表达式
-        generateSafePrimaryExpression(operands, operators, operandCount);
-      }
-    } while (result < 0 && attempts < 10);
-
-    // 如果还是负数，强制使用加法
-    if (result < 0) {
-      for (int i = 0; i < operators.size(); i++) {
-        operators.set(i, '+');
-      }
-      questionText = buildSimpleExpression(operands, operators);
-      result = evaluateSequential(operands, operators);
-    }
-
-    return generateIntOptions(questionText + " = ?", result, "小学");
-  }
-
-  private void generateSafePrimaryExpression(List<Integer> operands, List<Character> operators, int operandCount) {
-    operands.clear();
-    operators.clear();
-
-    // 首先生成所有操作数
-    for (int i = 0; i < operandCount; i++) {
-      operands.add(random.nextInt(100) + 1);
-    }
-
-    // 然后生成安全的运算符序列
-    int currentValue = operands.get(0);
-    for (int i = 1; i < operandCount; i++) {
-      char op;
-      if (currentValue < operands.get(i)) {
-        // 如果当前值小于下一个操作数，避免减法导致负数
-        if (random.nextBoolean()) {
-          op = '+';
-          currentValue += operands.get(i);
-        } else {
-          op = (random.nextBoolean() && currentValue > 0) ? '*' : '+';
-          if (op == '*') currentValue *= operands.get(i);
-          else currentValue += operands.get(i);
-        }
-      } else {
-        // 可以安全使用减法
-        op = getRandomOperation("+-*/");
-        switch (op) {
-          case '+': currentValue += operands.get(i); break;
-          case '-': currentValue -= operands.get(i); break;
-          case '*': currentValue *= operands.get(i); break;
-          case '/':
-            if (operands.get(i) != 0) currentValue /= operands.get(i);
-            else currentValue += operands.get(i);
-            break;
-        }
-      }
-      operators.add(op);
-    }
-  }
-
-  private Question generateMiddleSchoolQuestion(int index) {
-    int type = random.nextInt(4);
-    MathExpression expression = new MathExpression();
-
-    switch (type) {
-      case 0:
-        expression = createSquareExpression();
-        break;
-      case 1:
-        expression = createSqrtExpression();
-        break;
-      case 2:
-        expression = createSquareProductExpression();
-        break;
-      case 3:
-        expression = createSquareDivisionExpression();
-        break;
-    }
-
-    // 确保初中题目结果非负
-    if (expression.result < 0) {
-      expression = createSquareExpression(); // 重新生成一个肯定为正的题目
-    }
-
-    return generateIntOptions(expression.questionText + " = ?", expression.result, "初中");
-  }
-
-  private MathExpression createSquareExpression() {
-    int a = random.nextInt(10) + 1;
-    int b = random.nextInt(100) + 1;
-    int c = random.nextInt(100) + 1;
-    // 只使用加法确保结果为正
-    char op = '+';
-
-    String questionText = a + "² " + op + " " + b + " × " + c;
-    int result = a * a + b * c;
-
-    return new MathExpression(questionText, result);
-  }
-
-  private MathExpression createSqrtExpression() {
-    int sqrtBase = findPerfectSquare(100);
-    int sqrtVal = (int) Math.sqrt(sqrtBase);
-    int d = random.nextInt(100) + 1;
-    // 只使用加法确保结果为正
-    char op = '+';
-
-    String questionText = "√" + sqrtBase + " " + op + " " + d;
-    int result = sqrtVal + d;
-
-    return new MathExpression(questionText, result);
-  }
-
-  private MathExpression createSquareProductExpression() {
-    int e = random.nextInt(100) + 1;
-    int f = random.nextInt(10) + 1;
-    int g = random.nextInt(100) + 1;
-    // 只使用加法确保结果为正
-    char op = '+';
-
-    String questionText = e + " × " + f + "² " + op + " " + g;
-    int result = e * f * f + g;
-
-    return new MathExpression(questionText, result);
-  }
-
-  private MathExpression createSquareDivisionExpression() {
-    int h = random.nextInt(50) + 1;
-    int i = random.nextInt(50) + 1;
-    int sum = h + i;
-    int square = sum * sum;
-    int j = findDivisor(square);
-
-    String questionText = "(" + h + " + " + i + ")² ÷ " + j;
-    int result = square / j;
-
-    return new MathExpression(questionText, result);
-  }
-
-  private Question generateHighSchoolQuestion(int index) {
-    int type = random.nextInt(4);
-    TrigExpression expression = new TrigExpression();
-
-    switch (type) {
-      case 0:
-        expression = createSinExpression();
-        break;
-      case 1:
-        expression = createCosExpression();
-        break;
-      case 2:
-        expression = createTanExpression();
-        break;
-      case 3:
-        expression = createSinCosExpression();
-        break;
-    }
-
-    return generateDoubleOptions(expression.questionText + " = ?", expression.result, "高中");
-  }
-
-  private TrigExpression createSinExpression() {
-    String[] angles = {"0°", "30°", "45°", "60°", "90°"};
-    double[] sinValues = {0, 0.5, 0.71, 0.87, 1.0};
-
-    int idx = random.nextInt(angles.length);
-    int b = random.nextInt(100) + 1;
-    // 只使用加法确保结果为正
-    char op = '+';
-
-    String questionText = "sin(" + angles[idx] + ") " + op + " " + b;
-    double result = sinValues[idx] + b;
-
-    return new TrigExpression(questionText, result);
-  }
-
-  private TrigExpression createCosExpression() {
-    String[] angles = {"0°", "30°", "45°", "60°"};
-    double[] cosValues = {1.0, 0.87, 0.71, 0.5};
-
-    int idx = random.nextInt(angles.length);
-    int a = random.nextInt(100) + 1;
-
-    String questionText = a + " × cos(" + angles[idx] + ")";
-    double result = a * cosValues[idx];
-
-    return new TrigExpression(questionText, result);
-  }
-
-  private TrigExpression createTanExpression() {
-    String[] angles = {"0°", "30°", "45°", "60°"};
-    double[] tanValues = {0, 0.58, 1.0, 1.73};
-
-    int idx = random.nextInt(angles.length);
-    int c = random.nextInt(20) + 1;
-
-    String questionText = "tan(" + angles[idx] + ") ÷ " + c;
-    double result = tanValues[idx] / c;
-
-    return new TrigExpression(questionText, result);
-  }
-
-  private TrigExpression createSinCosExpression() {
-    String[] angles = {"0°", "30°", "45°", "60°"};
-    double[] sinValues = {0, 0.5, 0.71, 0.87};
-    double[] cosValues = {1.0, 0.87, 0.71, 0.5};
-
-    int idx1 = random.nextInt(angles.length);
-    int idx2 = random.nextInt(angles.length);
-    int d = random.nextInt(100) + 1;
-    // 只使用加法确保结果为正
-    char op = '+';
-
-    String questionText = "sin(" + angles[idx1] + ") × cos(" + angles[idx2] + ") " + op + " " + d;
-    double product = sinValues[idx1] * cosValues[idx2];
-    double result = product + d;
-
-    return new TrigExpression(questionText, result);
-  }
-
-  private char getRandomOperation(String operations) {
-    return operations.charAt(random.nextInt(operations.length()));
-  }
-
-  private String buildSimpleExpression(List<Integer> operands, List<Character> operators) {
-    StringBuilder sb = new StringBuilder();
-    for (int i = 0; i < operands.size(); i++) {
-      sb.append(operands.get(i));
-      if (i < operands.size() - 1) {
-        sb.append(" ").append(operators.get(i)).append(" ");
-      }
-    }
-    return sb.toString();
-  }
-
-  private String buildParenthesesExpression(List<Integer> operands, List<Character> operators, int parenPos) {
-    StringBuilder sb = new StringBuilder();
-    for (int i = 0; i < operands.size(); i++) {
-      if (i == parenPos) sb.append("(");
-      sb.append(operands.get(i));
-      if (i == parenPos + 1) sb.append(")");
-      if (i < operands.size() - 1) {
-        sb.append(" ").append(operators.get(i)).append(" ");
-      }
-    }
-    return sb.toString();
-  }
-
-  private int evaluateSequential(List<Integer> operands, List<Character> operators) {
-    int result = operands.get(0);
-    for (int i = 0; i < operators.size(); i++) {
-      result = calculate(result, operands.get(i + 1), operators.get(i));
-    }
-    return result;
-  }
-
-  private int evaluateWithParentheses(List<Integer> operands, List<Character> operators, int parenPos) {
-    int parenResult = calculate(operands.get(parenPos), operands.get(parenPos + 1), operators.get(parenPos));
-    List<Integer> newOperands = new ArrayList<>();
-    List<Character> newOperators = new ArrayList<>();
-
-    for (int i = 0; i < operands.size(); i++) {
-      if (i == parenPos) {
-        newOperands.add(parenResult);
-      } else if (i != parenPos + 1) {
-        newOperands.add(operands.get(i));
-      }
-    }
-
-    for (int i = 0; i < operators.size(); i++) {
-      if (i != parenPos) {
-        newOperators.add(operators.get(i));
-      }
-    }
-
-    return evaluateSequential(newOperands, newOperators);
-  }
-
-  private int calculate(int a, int b, char op) {
-    switch (op) {
-      case '+': return a + b;
-      case '-': return Math.max(a - b, 0);
-      case '*': return a * b;
-      case '/': return (b == 0) ? a : a / b;
-      default: return a + b;
-    }
-  }
-
-  private int findPerfectSquare(int max) {
-    List<Integer> squares = new ArrayList<>();
-    for (int i = 1; i * i <= max; i++) {
-      squares.add(i * i);
-    }
-    return squares.get(random.nextInt(squares.size()));
-  }
-
-  private int findDivisor(int number) {
-    List<Integer> divisors = new ArrayList<>();
-    for (int i = 2; i <= Math.min(20, number); i++) {
-      if (number % i == 0) {
-        divisors.add(i);
-      }
-    }
-    return divisors.isEmpty() ? 1 : divisors.get(random.nextInt(divisors.size()));
-  }
-
-  private Question generateIntOptions(String questionText, int answer, String level) {
-    String[] options = new String[4];
-    Set<Integer> usedValues = new HashSet<>();
-
-    String correctAnswer = String.valueOf(answer);
-    options[0] = correctAnswer;
-    usedValues.add(answer);
-
-    for (int i = 1; i < 4; i++) {
-      int wrongAnswer;
-      int attempts = 0;
-      do {
-        int range = Math.max(3, Math.abs(answer) / 5 + 1);
-        int offset = random.nextInt(range * 2 + 1) - range;
-        wrongAnswer = answer + offset;
-        wrongAnswer = Math.max(wrongAnswer, 0); // 确保错误答案也不为负
-        attempts++;
-        if (attempts > 20) {
-          wrongAnswer = answer + (i + 1) * 10 + 5;
-          break;
-        }
-      } while (wrongAnswer == answer || usedValues.contains(wrongAnswer));
-
-      options[i] = String.valueOf(wrongAnswer);
-      usedValues.add(wrongAnswer);
-    }
-
-    shuffleArray(options);
-    int correctIndex = findCorrectIndex(options, correctAnswer);
-
-    return new Question(questionText, options, correctIndex, level);
-  }
-
-  private Question generateDoubleOptions(String questionText, double answer, String level) {
-    String[] options = new String[4];
-    Set<String> usedValues = new HashSet<>();
-
-    String correctAnswer = formatDouble(answer);
-    options[0] = correctAnswer;
-    usedValues.add(correctAnswer);
-
-    for (int i = 1; i < 4; i++) {
-      String wrongAnswer;
-      int attempts = 0;
-      do {
-        double offset = (random.nextDouble() - 0.5) * Math.max(1, Math.abs(answer) * 0.3);
-        double wrongValue = answer + offset;
-        wrongAnswer = formatDouble(Math.max(wrongValue, 0)); // 确保错误答案不为负
-        attempts++;
-        if (attempts > 20) {
-          wrongAnswer = formatDouble(answer + (i + 1) * 2.5);
-          break;
-        }
-      } while (usedValues.contains(wrongAnswer) || wrongAnswer.equals(correctAnswer));
-
-      options[i] = wrongAnswer;
-      usedValues.add(wrongAnswer);
-    }
-
-    shuffleArray(options);
-    int correctIndex = findCorrectIndex(options, correctAnswer);
-
-    return new Question(questionText, options, correctIndex, level);
-  }
-
-  private String formatDouble(double value) {
-    if (Double.isInfinite(value)) return "∞";
-    if (Double.isNaN(value)) return "无解";
-    if (Math.abs(value) < 0.001) return "0";
-    return String.format("%.2f", value).replaceAll("0*$", "").replaceAll("\\.$", "");
-  }
-
-  private int findCorrectIndex(String[] options, String correctAnswer) {
-    for (int i = 0; i < options.length; i++) {
-      if (options[i].equals(correctAnswer)) return i;
-    }
-    return 0;
-  }
-
-  private void shuffleArray(String[] array) {
-    for (int i = array.length - 1; i > 0; i--) {
-      int index = random.nextInt(i + 1);
-      String temp = array[index];
-      array[index] = array[i];
-      array[i] = temp;
-    }
-  }
-
-  // 辅助类来存储题目和答案
-  private static class MathExpression {
-    String questionText;
-    int result;
-
-    MathExpression() {}
-
-    MathExpression(String questionText, int result) {
-      this.questionText = questionText;
-      this.result = result;
-    }
-  }
-
-  private static class TrigExpression {
-    String questionText;
-    double result;
-
-    TrigExpression() {}
-
-    TrigExpression(String questionText, double result) {
-      this.questionText = questionText;
-      this.result = result;
-    }
-  }
+public interface QuestionGenerator {
+  List<Question> generateQuestions(String level, int count);
 }
\ No newline at end of file
diff --git a/src/com/mathlearning/view/QuizFrame.java b/src/com/mathlearning/view/QuizFrame.java
index 48590cf..002e833 100644
--- a/src/com/mathlearning/view/QuizFrame.java
+++ b/src/com/mathlearning/view/QuizFrame.java
@@ -1,6 +1,5 @@
 package com.mathlearning.view;
 
-import com.mathlearning.controller.AuthController;
 import com.mathlearning.controller.QuestionController;
 import com.mathlearning.model.Question;
 import javax.swing.*;
@@ -58,12 +57,23 @@ public class QuizFrame extends JFrame {
     JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
     mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
 
-    // 进度条
+    // 顶部面板（退出按钮和进度条）
+    JPanel topPanel = new JPanel(new BorderLayout());
+
+    JButton exitButton = new JButton("退出答题");
+    exitButton.setFont(new Font("Microsoft YaHei", Font.PLAIN, 12));
+    exitButton.setBackground(new Color(220, 100, 100));
+    exitButton.setForeground(Color.WHITE);
+    exitButton.addActionListener(e -> exitQuiz());
+
     progressBar = new JProgressBar(0, totalQuestions);
     progressBar.setValue(0);
     progressBar.setStringPainted(true);
     progressBar.setFont(new Font("Microsoft YaHei", Font.PLAIN, 12));
-    mainPanel.add(progressBar, BorderLayout.NORTH);
+
+    topPanel.add(exitButton, BorderLayout.WEST);
+    topPanel.add(progressBar, BorderLayout.CENTER);
+    mainPanel.add(topPanel, BorderLayout.NORTH);
 
     // 问题面板
     JPanel questionPanel = new JPanel(new BorderLayout(10, 20));
@@ -84,7 +94,7 @@ public class QuizFrame extends JFrame {
     // 选项面板
     JPanel optionsPanel = new JPanel(new GridLayout(4, 1, 10, 10));
     optionsPanel.setBorder(
-        BorderFactory.createTitledBorder(BorderFactory.createLineBorder(Color.GRAY), "请选择答案"));
+            BorderFactory.createTitledBorder(BorderFactory.createLineBorder(Color.GRAY), "请选择答案"));
 
     optionButtons = new JRadioButton[4];
     buttonGroup = new ButtonGroup();
@@ -98,11 +108,11 @@ public class QuizFrame extends JFrame {
 
       final int index = i;
       optionButtons[i].addActionListener(
-          e -> {
-            // 保存当前选择
-            userSelections[currentDisplayIndex] = index;
-            System.out.println("用户选择: 第" + (currentDisplayIndex + 1) + "题 -> 选项" + index);
-          });
+              e -> {
+                // 保存当前选择
+                userSelections[currentDisplayIndex] = index;
+                System.out.println("用户选择: 第" + (currentDisplayIndex + 1) + "题 -> 选项" + index);
+              });
 
       buttonGroup.add(optionButtons[i]);
       optionsPanel.add(optionButtons[i]);
@@ -110,7 +120,6 @@ public class QuizFrame extends JFrame {
 
     JPanel optionsContainer = new JPanel(new FlowLayout(FlowLayout.CENTER));
     optionsContainer.add(optionsPanel);
-    mainPanel.add(optionsContainer, BorderLayout.SOUTH);
 
     // 控制面板
     JPanel controlPanel = new JPanel(new FlowLayout(FlowLayout.CENTER, 20, 10));
@@ -141,23 +150,7 @@ public class QuizFrame extends JFrame {
     // 添加事件监听器
     previousButton.addActionListener(new PreviousQuestionAction());
     nextButton.addActionListener(new NextQuestionAction());
-    // 添加顶部退出答题按钮
-    JPanel topPanel = new JPanel(new BorderLayout());
 
-    JButton exitButton = new JButton("退出答题");
-    exitButton.setFont(new Font("Microsoft YaHei", Font.PLAIN, 12));
-    exitButton.setBackground(new Color(220, 100, 100));
-    exitButton.setForeground(Color.WHITE);
-    exitButton.addActionListener(e -> exitQuiz());
-
-    progressBar = new JProgressBar(0, totalQuestions);
-    progressBar.setValue(0);
-    progressBar.setStringPainted(true);
-    progressBar.setFont(new Font("Microsoft YaHei", Font.PLAIN, 12));
-
-    topPanel.add(exitButton, BorderLayout.WEST);
-    topPanel.add(progressBar, BorderLayout.CENTER);
-    mainPanel.add(topPanel, BorderLayout.NORTH);
     add(mainPanel);
   }
 
@@ -168,16 +161,16 @@ public class QuizFrame extends JFrame {
     }
     Question currentQuestion = allQuestions.get(currentDisplayIndex);
     questionNumberLabel.setText(
-        String.format("第 %d 题 / 共 %d 题", currentDisplayIndex + 1, totalQuestions));
+            String.format("第 %d 题 / 共 %d 题", currentDisplayIndex + 1, totalQuestions));
     questionTextLabel.setText(
-        "<html><div style='text-align: center;'>"
-            + currentQuestion.getQuestionText()
-            + "</div></html>");
+            "<html><div style='text-align: center;'>"
+                    + currentQuestion.getQuestionText()
+                    + "</div></html>");
     String[] options = currentQuestion.getOptions();
     for (int i = 0; i < 4; i++) {
       String optionText =
-          String.format(
-              "<html><div style='padding: 5px;'>%c. %s</div></html>", (char) ('A' + i), options[i]);
+              String.format(
+                      "<html><div style='padding: 5px;'>%c. %s</div></html>", (char) ('A' + i), options[i]);
       optionButtons[i].setText(optionText);
     }
     buttonGroup.clearSelection(); // 清除当前选择状态
@@ -191,17 +184,17 @@ public class QuizFrame extends JFrame {
     // 更新进度条
     progressBar.setValue(currentDisplayIndex);
     progressBar.setString(
-        String.format(
-            "%d/%d (%.0f%%)",
-            currentDisplayIndex,
-            totalQuestions,
-            ((double) currentDisplayIndex / totalQuestions) * 100));
+            String.format(
+                    "%d/%d (%.0f%%)",
+                    currentDisplayIndex,
+                    totalQuestions,
+                    ((double) currentDisplayIndex / totalQuestions) * 100));
     updateButtonStates(); // 更新按钮状态
   }
 
   private void exitQuiz() {
     int result =
-        JOptionPane.showConfirmDialog(this, "确定要退出答题吗？所有进度将丢失。", "退出确认", JOptionPane.YES_NO_OPTION);
+            JOptionPane.showConfirmDialog(this, "确定要退出答题吗？所有进度将丢失。", "退出确认", JOptionPane.YES_NO_OPTION);
     if (result == JOptionPane.YES_OPTION) {
       parentFrame.setVisible(true);
       this.dispose();
@@ -245,8 +238,8 @@ public class QuizFrame extends JFrame {
       // 如果没有选择答案，提示用户但允许继续（除了最后一题）
       if (selectedIndex == -1) {
         int result =
-            JOptionPane.showConfirmDialog(
-                QuizFrame.this, "您还没有选择答案，确定要继续下一题吗？", "确认", JOptionPane.YES_NO_OPTION);
+                JOptionPane.showConfirmDialog(
+                        QuizFrame.this, "您还没有选择答案，确定要继续下一题吗？", "确认", JOptionPane.YES_NO_OPTION);
         if (result != JOptionPane.YES_OPTION) {
           return;
         }
@@ -262,52 +255,27 @@ public class QuizFrame extends JFrame {
     }
   }
 
-  private void submitAllAnswers() { // 直接在本地计算分数
-    final int calculatedScore = calculateLocalScore(); // 使用final
-    // 创建一个新的QuestionController来显示正确分数
-    questionController =
-        new QuestionController() {
-          @Override
-          public int getScore() {
-            return calculatedScore; // 现在可以访问了
-          }
-
-          @Override
-          public int getTotalQuestions() {
-            return totalQuestions;
-          }
-
-          @Override
-          public double getPercentage() {
-            return (double) calculatedScore / totalQuestions * 100;
-          }
-
-          @Override
-          public int[] getUserAnswers() {
-            return userSelections;
-          }
-
-          @Override
-          public java.util.List<Question> getCurrentQuestions() {
-            return allQuestions;
-          }
-        };
-  }
-
-  private int calculateLocalScore() {
+  private void submitAllAnswers() {
+    // 计算分数
     int score = 0;
     for (int i = 0; i < totalQuestions; i++) {
-      if (userSelections[i] != -1 && allQuestions.get(i).isCorrect(userSelections[i])) {
-        score++;
+      if (userSelections[i] != -1) {
+        // 使用 QuestionController 来检查答案
+        questionController.setCurrentQuestionIndex(i);
+        if (questionController.submitAnswer(userSelections[i])) {
+          score++;
+        }
       }
     }
-    return score;
+
+    // 重置到第一个问题，以便在结果显示时能正确访问
+    questionController.setCurrentQuestionIndex(0);
   }
 
   private void finishQuiz() {
-    ScoreFrame scoreFrame =
-        new ScoreFrame(questionController, userSelections, allQuestions, parentFrame);
+    // 使用原有的构造函数
+    ScoreFrame scoreFrame = new ScoreFrame(questionController, userSelections, allQuestions, parentFrame);
     scoreFrame.setVisible(true);
     this.dispose();
   }
-}
+} // 添加这个闭合大括号
\ No newline at end of file
diff --git a/src/com/mathlearning/view/ScoreFrame.java b/src/com/mathlearning/view/ScoreFrame.java
index 9e93212..21e9edc 100644
--- a/src/com/mathlearning/view/ScoreFrame.java
+++ b/src/com/mathlearning/view/ScoreFrame.java
@@ -13,10 +13,10 @@ public class ScoreFrame extends JFrame {
   private LevelSelectionFrame parentFrame;
 
   public ScoreFrame(
-      QuestionController questionController,
-      int[] userSelections,
-      List<Question> allQuestions,
-      LevelSelectionFrame parent) {
+          QuestionController questionController,
+          int[] userSelections,
+          List<Question> allQuestions,
+          LevelSelectionFrame parent) {
     this.parentFrame = parent;
     this.questionController = questionController;
     this.userSelections = userSelections;
@@ -34,13 +34,13 @@ public class ScoreFrame extends JFrame {
     JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
     mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
 
-    // Score summary
+    // Score summary - 修复这里
     int score = questionController.getScore();
     int total = questionController.getTotalQuestions();
-    double percentage = questionController.getPercentage();
+    double percentage = (double) score / total * 100; // 手动计算百分比
 
     JLabel scoreLabel =
-        new JLabel(String.format("得分: %d/%d (%.1f%%)", score, total, percentage), JLabel.CENTER);
+            new JLabel(String.format("得分: %d/%d (%.1f%%)", score, total, percentage), JLabel.CENTER);
     scoreLabel.setFont(new Font("Microsoft YaHei", Font.BOLD, 24));
 
     Color color;
@@ -62,21 +62,22 @@ public class ScoreFrame extends JFrame {
     for (int i = 0; i < allQuestions.size(); i++) {
       Question q = allQuestions.get(i);
       int userAnswer = userSelections[i];
-      boolean isCorrect = (userAnswer != -1) && q.isCorrect(userAnswer);
+      // 修复这里：使用 getCorrectIndex() 而不是 getCorrectAnswerIndex()
+      boolean isCorrect = (userAnswer != -1) && (userAnswer == q.getCorrectIndex());
 
       details.append(String.format("第%d题: %s\n", i + 1, q.getQuestionText()));
       details.append(
-          String.format(
-              "你的答案: %s\n",
-              userAnswer == -1
-                  ? "未作答"
-                  : (char) ('A' + userAnswer) + ". " + q.getOptions()[userAnswer]));
+              String.format(
+                      "你的答案: %s\n",
+                      userAnswer == -1
+                              ? "未作答"
+                              : (char) ('A' + userAnswer) + ". " + q.getOptions()[userAnswer]));
       details.append(
-          String.format(
-              "正确答案: %s\n",
-              (char) ('A' + q.getCorrectAnswerIndex())
-                  + ". "
-                  + q.getOptions()[q.getCorrectAnswerIndex()]));
+              String.format(
+                      "正确答案: %s\n",
+                      (char) ('A' + q.getCorrectIndex())
+                              + ". "
+                              + q.getOptions()[q.getCorrectIndex()]));
       details.append(isCorrect ? "✓ 正确\n" : "✗ 错误\n");
       details.append("--------------------\n");
     }
@@ -108,4 +109,4 @@ public class ScoreFrame extends JFrame {
     parentFrame.setVisible(true);
     this.dispose();
   }
-}
+}
\ No newline at end of file