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

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/services/MathQuestion.java

@@ -8,27 +8,28 @@ 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() {
-        int operandCount = random.nextInt(5) + 1;
         StringBuilder question = new StringBuilder();
 
         switch (difficulty) {
             case PRIMARY:
-                question.append(generatePrimaryQuestion(operandCount));
+                question.append(generatePrimaryQuestion());
                 break;
             case JUNIOR:
-                question.append(generateJuniorQuestion(operandCount));
+                question.append(generateJuniorQuestion());
                 break;
             case SENIOR:
-                question.append(generateSeniorQuestion(operandCount));
+                question.append(generateSeniorQuestion());
                 break;
         }
 
@@ -38,7 +39,33 @@ public class MathQuestion implements QuestionInterface {
 
     @Override
     public boolean isValid() {
-        return questionText != null && !questionText.trim().isEmpty();
+        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
@@ -51,7 +78,9 @@ public class MathQuestion implements QuestionInterface {
         return difficulty;
     }
 
-    private String generatePrimaryQuestion(int operandCount) {
+    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();
 
@@ -61,6 +90,7 @@ public class MathQuestion implements QuestionInterface {
             }
             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(")");
             }
@@ -68,19 +98,51 @@ public class MathQuestion implements QuestionInterface {
         return question.toString();
     }
 
-    private String generateJuniorQuestion(int operandCount) {
-        String question = generatePrimaryQuestion(operandCount);
-        if (random.nextBoolean()) {
-            return "√" + (random.nextInt(100) + 1) + " + " + question;
-        } else {
-            return "(" + (random.nextInt(10) + 1) + ")² + " + question;
+    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(int operandCount) {
-        String question = generatePrimaryQuestion(operandCount);
+    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"};
-        return trigFunctions[random.nextInt(trigFunctions.length)] +
-                "(" + (random.nextInt(90) + 1) + "°) + " + question;
+
+        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

@@ -31,7 +31,8 @@ public class QuestionGenerator {
                     return null;
                 }
             } while (existingQuestions.contains(question.getQuestionText()) ||
-                    newQuestions.contains(question.getQuestionText()));
+                    newQuestions.contains(question.getQuestionText()) ||
+                    !question.isValid());
 
             newQuestions.add(question.getQuestionText());
             questions[i] = (i + 1) + ". " + question.getQuestionText();