diff --git a/doc/readme.md b/doc/readme.md
index 1a64046..241b61d 100644
--- a/doc/readme.md
+++ b/doc/readme.md
@@ -9,3 +9,5 @@
 [Console]::InputEncoding = [Console]::OutputEncoding = [System.Text.Encoding]::UTF8
 
 **3**.运行时会生成若干文件夹用于存储试题；
+
+4.编译版本为C++11以上
diff --git a/src/main.cpp b/src/main.cpp
index ba76e19..c8cd0f0 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -12,6 +12,7 @@
 #include <dirent.h>
 #include <sys/stat.h>
 #include <cmath>
+#include <memory>
 
 #ifdef _WIN32
     #include <direct.h>
@@ -20,21 +21,289 @@
 
 using namespace std;
 
-// 账户结构体
+// 账户结构体：存储用户账户信息
 struct Account {
-    string username;
-    string password;
-    string type; // 用户类型：小学、初中、高中
+    string username;  // 用户名
+    string password;  // 密码
+    string type;      // 用户类型：小学、初中、高中
 };
 
-// 数学卷子生成主类
+// 抽象题目生成器：定义题目生成器的统一接口
+class MathQuestionGenerator {
+public:
+    virtual ~MathQuestionGenerator() {}
+    virtual std::string generateQuestion() = 0;  // 生成题目的纯虚函数
+};
+
+// 小学题目生成器：生成小学级别的数学题目
+class PrimaryQuestionGenerator : public MathQuestionGenerator {
+public:
+    PrimaryQuestionGenerator() {}
+    
+    // 生成指定范围内的随机数
+    int randomNumber(int min, int max) {
+        return rand() % (max - min + 1) + min;
+    }
+    
+    // 构建数学表达式字符串
+    std::string buildExpression(const std::vector<int>& operands, const std::vector<char>& operators) {
+        size_t n = operands.size();
+        // 简单情况：只有两个操作数
+        if (n == 2) {
+            return std::to_string(operands[0]) + " " + std::string(1, operators[0]) + " " + std::to_string(operands[1]);
+        }
+        
+        // 随机选择括号位置
+        size_t l = 1, r = n - 2;
+        if (r > l) {
+            l = 1 + rand() % (n - 2);
+            size_t max_r = n - 2;
+            size_t range = max_r - l;
+            if (range == 0) {
+                r = l + 1;
+            } else {
+                r = l + 1 + rand() % range;
+            }
+        } else {
+            l = 1;
+            r = 2;
+        }
+        
+        // 构建带括号的表达式
+        std::string expression;
+        for (size_t i = 0; i < n; i++) {
+            if (i == l) expression += "(";
+            expression += std::to_string(operands[i]);
+            if (i < operators.size()) {
+                expression += " " + std::string(1, operators[i]) + " ";
+            }
+            if (i == r) expression += ")";
+        }
+        return expression;
+    }
+    
+    // 生成小学题目：包含加减乘除运算，支持括号
+    std::string generateQuestion() override {
+        int operandCount = randomNumber(2, 5);  // 操作数数量：2-5个
+        std::vector<int> operands;
+        std::vector<char> operators;
+        
+        // 生成第一个操作数
+        operands.push_back(randomNumber(1, 100));
+        
+        // 生成后续操作数和运算符
+        for (int i = 0; i < operandCount - 1; i++) {
+            int opType = randomNumber(0, 3);  // 随机选择运算符类型
+            int prev = operands.back();
+            int next;
+            
+            switch (opType) {
+                case 0:  // 加法
+                    next = randomNumber(1, 100);
+                    operators.push_back('+');
+                    operands.push_back(next);
+                    break;
+                case 1:  // 减法（确保结果非负）
+                    next = randomNumber(1, prev);
+                    operators.push_back('-');
+                    operands.push_back(next);
+                    break;
+                case 2:  // 乘法
+                    next = randomNumber(1, 100);
+                    operators.push_back('*');
+                    operands.push_back(next);
+                    break;
+                case 3:  // 除法（确保能整除）
+                    next = randomNumber(1, 10);
+                    int result = randomNumber(1, 10);
+                    int dividend = next * result;
+                    operands.back() = dividend;  // 修改被除数以确保整除
+                    operators.push_back('/');
+                    operands.push_back(next);
+                    break;
+            }
+        }
+        return buildExpression(operands, operators);
+    }
+};
+
+// 初中题目生成器：生成初中级别的数学题目（包含平方和开方）
+class MiddleQuestionGenerator : public MathQuestionGenerator {
+public:
+    MiddleQuestionGenerator() {}
+    
+    // 生成指定范围内的随机数
+    int randomNumber(int min, int max) {
+        return rand() % (max - min + 1) + min;
+    }
+    
+    // 生成初中题目：包含平方和开方运算
+    std::string generateQuestion() override {
+        int operandCount = randomNumber(2, 5);
+        std::vector<std::string> items;
+        bool hasSquareOrRoot = false;  // 标记是否已包含平方或开方
+        
+        // 生成操作数项
+        for (int i = 0; i < operandCount; i++) {
+            int opType = randomNumber(0, 2);
+            // 确保至少有一个平方或开方运算
+            if ((!hasSquareOrRoot && i == operandCount - 1) || (opType > 0 && !hasSquareOrRoot)) {
+                if (opType == 1) {
+                    items.push_back(std::to_string(randomNumber(1, 100)) + "²");  // 平方
+                } else {
+                    items.push_back("√" + std::to_string(randomNumber(1, 100)));  // 开方
+                }
+                hasSquareOrRoot = true;
+            } else {
+                items.push_back(std::to_string(randomNumber(1, 100)));  // 普通数字
+            }
+        }
+        
+        // 生成运算符
+        std::vector<std::string> ops;
+        for (int i = 1; i < operandCount; i++) {
+            int opType = randomNumber(0, 3);
+            switch (opType) {
+                case 0: ops.push_back("+"); break;
+                case 1: ops.push_back("-"); break;
+                case 2: ops.push_back("*"); break;
+                case 3: ops.push_back("/"); break;
+            }
+        }
+        
+        // 找到可以加括号的位置（普通数字位置）
+        std::vector<int> validIdx;
+        for (int i = 0; i < operandCount; i++) {
+            if (items[i].find("²") == std::string::npos && items[i].find("√") == std::string::npos) {
+                validIdx.push_back(i);
+            }
+        }
+        
+        // 随机选择括号位置
+        int l = 0, r = 0;
+        if (validIdx.size() > 1) {
+            l = validIdx[rand() % (validIdx.size() - 1)];
+            int range = validIdx.size() - (l + 1);
+            if (range == 0) {
+                r = l + 1;
+            } else {
+                r = l + 1 + rand() % range;
+            }
+        }
+        
+        // 构建表达式
+        std::string expr;
+        for (int i = 0; i < operandCount; i++) {
+            if (i == l && validIdx.size() > 1) expr += "(";
+            expr += items[i];
+            if (i == r && validIdx.size() > 1) expr += ")";
+            if (i < ops.size()) expr += " " + ops[i] + " ";
+        }
+        
+        // 如果没有括号，给整个表达式加括号
+        if (expr.find('(') == std::string::npos && validIdx.size() > 1) expr = "(" + expr + ")";
+        return expr;
+    }
+};
+
+// 高中题目生成器：生成高中级别的数学题目（包含三角函数）
+class HighQuestionGenerator : public MathQuestionGenerator {
+public:
+    HighQuestionGenerator() {}
+    
+    // 生成指定范围内的随机数
+    int randomNumber(int min, int max) {
+        return rand() % (max - min + 1) + min;
+    }
+    
+    // 生成高中题目：包含三角函数、平方和开方运算
+    std::string generateQuestion() override {
+        int operandCount = randomNumber(2, 5);
+        std::vector<std::string> items;
+        bool hasTrigonometry = false;  // 标记是否已包含三角函数
+        
+        // 生成操作数项
+        for (int i = 0; i < operandCount; i++) {
+            int opType = randomNumber(0, 5);
+            // 确保至少有一个三角函数
+            if ((!hasTrigonometry && i == operandCount - 1) || (opType >= 3 && !hasTrigonometry)) {
+                int trigType = randomNumber(0, 2);
+                switch (trigType) {
+                    case 0: items.push_back("sin(" + std::to_string(randomNumber(1, 100)) + ")"); break;
+                    case 1: items.push_back("cos(" + std::to_string(randomNumber(1, 100)) + ")"); break;
+                    case 2: items.push_back("tan(" + std::to_string(randomNumber(1, 100)) + ")"); break;
+                }
+                hasTrigonometry = true;
+            } else if (opType == 1) {
+                items.push_back(std::to_string(randomNumber(1, 100)) + "²");  // 平方
+            } else if (opType == 2) {
+                items.push_back("√" + std::to_string(randomNumber(1, 100)));  // 开方
+            } else {
+                items.push_back(std::to_string(randomNumber(1, 100)));  // 普通数字
+            }
+        }
+        
+        // 生成运算符
+        std::vector<std::string> ops;
+        for (int i = 1; i < operandCount; i++) {
+            int opType = randomNumber(0, 3);
+            switch (opType) {
+                case 0: ops.push_back("+"); break;
+                case 1: ops.push_back("-"); break;
+                case 2: ops.push_back("*"); break;
+                case 3: ops.push_back("/"); break;
+            }
+        }
+        
+        // 找到可以加括号的位置（非三角函数位置）
+        std::vector<int> validIdx;
+        for (int i = 0; i < operandCount; i++) {
+            if (items[i].find("sin(") == std::string::npos && 
+                items[i].find("cos(") == std::string::npos && 
+                items[i].find("tan(") == std::string::npos) {
+                validIdx.push_back(i);
+            }
+        }
+        
+        // 随机选择括号位置
+        int l = -1, r = -1;
+        if (validIdx.size() > 1) {
+            int idx1 = rand() % validIdx.size();
+            int idx2;
+            do {
+                idx2 = rand() % validIdx.size();
+            } while (idx1 == idx2);
+            
+            if (validIdx[idx1] < validIdx[idx2]) {
+                l = validIdx[idx1];
+                r = validIdx[idx2];
+            } else {
+                l = validIdx[idx2];
+                r = validIdx[idx1];
+            }
+        }
+        
+        // 构建表达式
+        std::string expr;
+        for (int i = 0; i < operandCount; i++) {
+            if (i == l) expr += "(";
+            expr += items[i];
+            if (i == r) expr += ")";
+            if (i < ops.size()) expr += " " + ops[i] + " ";
+        }
+        return expr;
+    }
+};
+
+// 数学卷子生成主类：管理用户登录、题目生成、文件保存等核心功能
 class MathPaperGenerator {
 private:
-    vector<Account> accounts; // 所有账户信息
-    string currentUser;       // 当前登录用户
-    string currentType;       // 当前题目类型
-    bool isLoggedIn;          // 登录状态
-    map<string, set<string>> userQuestions; // 用户已生成题目集合（防止重复）
+    vector<Account> accounts;           // 存储所有账户信息
+    string currentUser;                 // 当前登录用户
+    string currentType;                 // 当前题目类型
+    bool isLoggedIn;                    // 登录状态标记
+    map<string, set<string>> userQuestions;  // 用户已生成题目记录（用于查重）
+    MathQuestionGenerator* questionGenerator;  // 题目生成器指针
 
     // 创建目录
     bool createDirectory(const string& path) {
@@ -68,7 +337,7 @@ private:
         return files;
     }
     
-    // 去除字符串首尾空白
+    // 去除字符串首尾空白字符
     string trim(const string& str) {
         size_t start = str.find_first_not_of(" \t\n\r");
         size_t end = str.find_last_not_of(" \t\n\r");
@@ -78,44 +347,10 @@ private:
         return str.substr(start, end - start + 1);
     }
     
-    // 生成[min, max]范围的随机数
-    int randomNumber(int min, int max) {
-        return rand() % (max - min + 1) + min;
-    }
-    
-public:
-    // 构造函数，初始化账户并创建用户文件夹
-    MathPaperGenerator() {
-        isLoggedIn = false;
-        currentUser = "";
-        currentType = "";
-        
-        accounts = {
-            {"张三1", "123", "小学"},
-            {"张三2", "123", "小学"},
-            {"张三3", "123", "小学"},
-            {"李四1", "123", "初中"},
-            {"李四2", "123", "初中"},
-            {"李四3", "123", "初中"},
-            {"王五1", "123", "高中"},
-            {"王五2", "123", "高中"},
-            {"王五3", "123", "高中"}
-        };
-        
-        for (const auto& account : accounts) {
-            string folderPath = account.username;
-            if (!directoryExists(folderPath)) {
-                createDirectory(folderPath);
-            }
-            loadUserQuestions(account.username);
-        }
-    }
-    
     // 加载用户已生成题目（防止重复）
     void loadUserQuestions(const string& username) {
         userQuestions[username].clear();
         string folderPath = username;
-        
         if (!directoryExists(folderPath)) {
             return;
         }
@@ -139,307 +374,114 @@ public:
             }
         }
     }
-    
-    // 用户登录
-    bool login(const string& username, const string& password) {
-        for (const auto& account : accounts) {
-            if (account.username == username && account.password == password) {
-                currentUser = username;
-                currentType = account.type;
-                isLoggedIn = true;
-                return true;
-            }
-        }
-        return false;
-    }
-    
-    // 注销
-    void logout() {
+
+public:
+    // 构造函数：初始化账户、创建用户目录、加载历史题目
+    MathPaperGenerator() {
         isLoggedIn = false;
         currentUser = "";
         currentType = "";
-    }
-    
-    // 切换题目类型
-    bool switchType(const string& type) {
-        string trimmedType = trim(type);
-        if (trimmedType == "小学" || trimmedType == "初中" || trimmedType == "高中") {
-            currentType = trimmedType;
-            return true;
-        }
-        return false;
-    }
-    
-    // 生成小学题目（仅加减乘除）
-    string generatePrimaryQuestion() {
-        int operandCount = randomNumber(2, 5);
-        vector<int> operands;
-        vector<char> operators;
         
-        // 先生成第一个操作数
-        operands.push_back(randomNumber(1, 100));
+        // 初始化预设账户
+        accounts = {
+            {"张三1", "123", "小学"},
+            {"张三2", "123", "小学"},
+            {"张三3", "123", "小学"},
+            {"李四1", "123", "初中"},
+            {"李四2", "123", "初中"},
+            {"李四3", "123", "初中"},
+            {"王五1", "123", "高中"},
+            {"王五2", "123", "高中"},
+            {"王五3", "123", "高中"}
+        };
         
-        for (int i = 0; i < operandCount - 1; i++) {
-            int opType = randomNumber(0, 3);
-            int prev = operands.back();
-            int next;
-            switch (opType) {
-                case 0: // 加法
-                    next = randomNumber(1, 100);
-                    operators.push_back('+');
-                    operands.push_back(next);
-                    break;
-                case 1: // 减法，保证前一个数大于等于后一个数
-                    next = randomNumber(1, prev);
-                    operators.push_back('-');
-                    operands.push_back(next);
-                    break;
-                case 2: // 乘法
-                    next = randomNumber(1, 100);
-                    operators.push_back('*');
-                    operands.push_back(next);
-                    break;
-                case 3: // 除法，保证能整除且结果为正整数
-                    {
-                        // 先随机一个除数，不能为0
-                        next = randomNumber(1, 10);
-                        int result = randomNumber(1, 10);
-                        int dividend = next * result;
-                        // dividend 作为前一个数，next 作为后一个数
-                        operands.back() = dividend;
-                        operators.push_back('/');
-                        operands.push_back(next);
-                    }
-                    break;
+        // 创建用户目录并加载历史题目
+        for (const auto& account : accounts) {
+            string folderPath = account.username;
+            if (!directoryExists(folderPath)) {
+                createDirectory(folderPath);
             }
+            loadUserQuestions(account.username);
         }
         
-        return buildExpression(operands, operators);
+        questionGenerator = nullptr;
     }
-    
-    // 生成初中题目（加减乘除+平方/根号）
-    string generateMiddleQuestion() {
-        int operandCount = randomNumber(2, 5);
-        vector<int> operands;
-        vector<string> operators; // 使用string以支持平方和根号
-        
-        for (int i = 0; i < operandCount; i++) {
-            operands.push_back(randomNumber(1, 100));
-        }
-        
-        // 确保至少有一个平方或根号
-        bool hasSquareOrRoot = false;
+
+    // 切换题目类型：小学/初中/高中
+    bool switchType(const string& type) {
+        string trimmedType = trim(type);
         
-        // 构建表达式
-        string expression = "";
-        for (int i = 0; i < operandCount; i++) {
-            if (i > 0) {
-                int opType = randomNumber(0, 3);
-                switch (opType) {
-                    case 0: expression += " + "; break;
-                    case 1: expression += " - "; break;
-                    case 2: expression += " * "; break;
-                    case 3: expression += " / "; break;
-                }
-            }
-            
-            // 随机决定是否添加平方或根号（确保至少有一个）
-            int specialOp = randomNumber(0, 3);
-            if ((!hasSquareOrRoot && i == operandCount - 1) || (specialOp == 0 && i < operandCount - 1)) {
-                // 添加平方或根号
-                if (randomNumber(0, 1) == 0) {
-                    expression += to_string(operands[i]) + "²"; // 平方
-                } else {
-                    expression += "√" + to_string(operands[i]); // 根号
-                }
-                hasSquareOrRoot = true;
-            } else {
-                expression += to_string(operands[i]);
-            }
+        // 清理旧的生成器
+        if (questionGenerator) {
+            delete questionGenerator;
+            questionGenerator = nullptr;
         }
         
-        // 如果还没有平方或根号，强制添加一个
-        if (!hasSquareOrRoot) {
-            int pos = randomNumber(0, operandCount - 1);
-            size_t numStart = 0;
-            for (int i = 0; i < pos; i++) {
-                size_t opPos = expression.find_first_of("+-*/", numStart);
-                if (opPos != string::npos) {
-                    numStart = opPos + 3; // 跳过运算符和空格
-                }
-            }
-            
-            // 在指定位置插入平方或根号
-            if (randomNumber(0, 1) == 0) {
-                expression.insert(numStart, "(");
-                size_t insertPos = expression.find(' ', numStart);
-                if (insertPos == string::npos) {
-                    insertPos = expression.size();
-                }
-                expression.insert(insertPos, ")²");
-            } else {
-                expression.insert(numStart, "√(");
-                size_t insertPos = expression.find(' ', numStart);
-                if (insertPos == string::npos) {
-                    insertPos = expression.size();
-                }
-                expression.insert(insertPos, ")");
-            }
+        // 根据类型创建相应的题目生成器
+        if (trimmedType == "小学") {
+            currentType = trimmedType;
+            questionGenerator = new PrimaryQuestionGenerator();
+            return true;
+        } else if (trimmedType == "初中") {
+            currentType = trimmedType;
+            questionGenerator = new MiddleQuestionGenerator();
+            return true;
+        } else if (trimmedType == "高中") {
+            currentType = trimmedType;
+            questionGenerator = new HighQuestionGenerator();
+            return true;
         }
-        
-        return expression;
+        return false;
     }
-    
-    // 生成高中题目（加减乘除+平方/根号+三角函数）
-    string generateHighQuestion() {
-        int operandCount = randomNumber(2, 5);
-        vector<int> operands;
-        
-        for (int i = 0; i < operandCount; i++) {
-            operands.push_back(randomNumber(1, 100));
-        }
-        
-        // 确保至少有一个三角函数
-        bool hasTrigonometry = false;
-        
-        // 构建表达式
-        string expression = "";
-        for (int i = 0; i < operandCount; i++) {
-            if (i > 0) {
-                int opType = randomNumber(0, 3);
-                switch (opType) {
-                    case 0: expression += " + "; break;
-                    case 1: expression += " - "; break;
-                    case 2: expression += " * "; break;
-                    case 3: expression += " / "; break;
-                }
-            }
-            
-            // 随机决定是否添加平方、根号或三角函数
-            int specialOp = randomNumber(0, 5);
-            if ((!hasTrigonometry && i == operandCount - 1) || specialOp >= 2) {
-                // 添加特殊运算
-                int opChoice = randomNumber(0, 4);
-                switch (opChoice) {
-                    case 0: // 平方
-                        expression += to_string(operands[i]) + "²";
-                        break;
-                    case 1: // 根号
-                        expression += "√" + to_string(operands[i]);
-                        break;
-                    case 2: // sin
-                        expression += "sin(" + to_string(operands[i]) + ")";
-                        hasTrigonometry = true;
-                        break;
-                    case 3: // cos
-                        expression += "cos(" + to_string(operands[i]) + ")";
-                        hasTrigonometry = true;
-                        break;
-                    case 4: // tan
-                        expression += "tan(" + to_string(operands[i]) + ")";
-                        hasTrigonometry = true;
-                        break;
-                }
-            } else {
-                expression += to_string(operands[i]);
-            }
-        }
-        
-        // 如果还没有三角函数，强制添加一个
-        if (!hasTrigonometry) {
-            int pos = randomNumber(0, operandCount - 1);
-            size_t numStart = 0;
-            for (int i = 0; i < pos; i++) {
-                size_t opPos = expression.find_first_of("+-*/", numStart);
-                if (opPos != string::npos) {
-                    numStart = opPos + 3; // 跳过运算符和空格
-                }
-            }
-            
-            // 在指定位置插入三角函数
-            int trigChoice = randomNumber(0, 2);
-            size_t insertPos;
-            switch (trigChoice) {
-                case 0: 
-                    expression.insert(numStart, "sin(");
-                    insertPos = expression.find(' ', numStart);
-                    if (insertPos == string::npos) {
-                        insertPos = expression.size();
-                    }
-                    expression.insert(insertPos, ")");
-                    break;
-                case 1:
-                    expression.insert(numStart, "cos(");
-                    insertPos = expression.find(' ', numStart);
-                    if (insertPos == string::npos) {
-                        insertPos = expression.size();
-                    }
-                    expression.insert(insertPos, ")");
-                    break;
-                case 2:
-                    expression.insert(numStart, "tan(");
-                    insertPos = expression.find(' ', numStart);
-                    if (insertPos == string::npos) {
-                        insertPos = expression.size();
-                    }
-                    expression.insert(insertPos, ")");
-                    break;
+
+    // 用户登录验证
+    bool login(const string& username, const string& password) {
+        for (const auto& account : accounts) {
+            if (account.username == username && account.password == password) {
+                currentUser = username;
+                currentType = account.type;
+                isLoggedIn = true;
+                switchType(currentType);  // 根据用户类型初始化题目生成器
+                return true;
             }
         }
-        
-        return expression;
-    }
-    
-    // 构建表达式
-    string buildExpression(const vector<int>& operands, const vector<char>& operators) {
-        // 构建表达式，保证顺序与生成一致
-        string expression = to_string(operands[0]);
-        for (size_t i = 0; i < operators.size(); i++) {
-            expression += " " + string(1, operators[i]) + " " + to_string(operands[i + 1]);
-        }
-        return expression;
-    }
-    
-    // 判断题目是否重复
-    bool isQuestionDuplicate(const string& question) {
-        return userQuestions[currentUser].find(question) != userQuestions[currentUser].end();
+        return false;
     }
-    
-    // 生成指定数量题目
+
+    // 生成指定数量的题目
     vector<string> generateQuestions(int count) {
         vector<string> questions;
-        set<string> generatedSet;
+        set<string> generatedSet;  // 本次生成题目的临时集合
         int attempts = 0;
-        const int MAX_ATTEMPTS = count * 10;
+        const int MAX_ATTEMPTS = count * 10;  // 最大尝试次数防止无限循环
         
+        // 生成不重复的题目
         while (questions.size() < count && attempts < MAX_ATTEMPTS) {
             string question;
-            
-            if (currentType == "小学") {
-                question = generatePrimaryQuestion();
-            } else if (currentType == "初中") {
-                question = generateMiddleQuestion();
-            } else if (currentType == "高中") {
-                question = generateHighQuestion();
+            if (questionGenerator) {
+                question = questionGenerator->generateQuestion();
+            } else {
+                question = "";
             }
             
+            // 检查题目是否重复
             if (!isQuestionDuplicate(question) && generatedSet.find(question) == generatedSet.end()) {
                 questions.push_back(question);
                 generatedSet.insert(question);
-                userQuestions[currentUser].insert(question);
+                userQuestions[currentUser].insert(question);  // 添加到用户历史记录
             }
             attempts++;
         }
         
-        // 如果无法生成足够的不重复题目，用简单题目填充
+        // 如果无法生成足够的不重复题目，使用备用方案
         while (questions.size() < count) {
             string question;
             if (currentType == "小学") {
-                question = to_string(randomNumber(1, 100)) + " + " + to_string(randomNumber(1, 100));
+                question = to_string(rand() % 100 + 1) + " + " + to_string(rand() % 100 + 1);
             } else if (currentType == "初中") {
-                question = to_string(randomNumber(1, 100)) + "² + " + to_string(randomNumber(1, 100));
+                question = to_string(rand() % 100 + 1) + "² + " + to_string(rand() % 100 + 1);
             } else {
-                question = "sin(" + to_string(randomNumber(1, 100)) + ") + " + to_string(randomNumber(1, 100));
+                question = "sin(" + to_string(rand() % 100 + 1) + ") + " + to_string(rand() % 100 + 1);
             }
             
             if (!isQuestionDuplicate(question)) {
@@ -450,102 +492,76 @@ public:
         
         return questions;
     }
-    
-    // 保存题目到文件
-    void saveQuestions(const vector<string>& questions) {
-        time_t now = time(nullptr);
-        tm* localTime = localtime(&now);
-        
-        stringstream filename;
-        filename << setfill('0') 
-                << localTime->tm_year + 1900 << "-"
-                << setw(2) << localTime->tm_mon + 1 << "-"
-                << setw(2) << localTime->tm_mday << "-"
-                << setw(2) << localTime->tm_hour << "-"
-                << setw(2) << localTime->tm_min << "-"
-                << setw(2) << localTime->tm_sec << ".txt";
-        
-        string filepath = currentUser + "/" + filename.str();
-        ofstream file(filepath, ios::binary);
-        
-        if (file.is_open()) {
-            unsigned char bom[] = {0xEF, 0xBB, 0xBF};
-            file.write((char*)bom, 3);
-            for (size_t i = 0; i < questions.size(); i++) {
-                string line = to_string(i + 1) + ". " + questions[i] + "\n";
-                file.write(line.c_str(), line.size());
-                if (i < questions.size() - 1) {
-                    file.write("\n", 1);
-                }
-            }
-            file.close();
-            cout << "题目已保存到: " << filepath << endl;
-        } else {
-            cout << "文件保存失败!" << endl;
-        }
+
+    // 检查题目是否重复
+    bool isQuestionDuplicate(const string& question) {
+        return userQuestions[currentUser].find(question) != userQuestions[currentUser].end();
+    }
+
+private:
+    // 提示用户输入题目数量或切换类型
+    void promptTypeAndCount() {
+        cout << endl << "准备生成" << currentType << "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）" << endl;
+        cout << "或者输入\"切换为小学/初中/高中\"来切换题目类型: ";
     }
     
-    // 处理用户输入
-    void processInput() {
-        string input;
-        getline(cin, input);
-        
-        input = trim(input);
-        
-        if (input == "-1") {
-            logout();
-            return;
-        }
-        
-        if (input.find("切换为") == 0) {
-            string type = input.substr(9);
-            type = trim(type);
-            
-            if (switchType(type)) {
-                cout << "切换成功！当前类型为：" << currentType << endl;
-                cout << "准备生成" << currentType << "数学题目，请输入生成题目数量: ";
-                getline(cin, input);
-                processCountInput(input);
-            } else {
-                cout << "请输入小学、初中和高中三个选项中的一个" << endl;
-            }
-            return;
+    // 处理类型切换命令
+    void handleSwitchType(const string& type) {
+        if (switchType(type)) {
+            cout << "切换成功！当前类型为：" << currentType << endl;
+            promptTypeAndCount();
+            string input;
+            getline(cin, input);
+            processCountInput(input);
+        } else {
+            cout << "请输入小学、初中和高中三个选项中的一个" << endl;
         }
-        
-        processCountInput(input);
     }
     
-    // 处理题目数量输入
-    void processCountInput(const string& input) {
-        //*
+    // 处理数量输入
+    void handleCountInput(const string& trimmedInput) {
         try {
-        //*/
-            int count = stoi(input);
+            int count = stoi(trimmedInput);
             if (count >= 10 && count <= 30) {
                 vector<string> questions = generateQuestions(count);
                 saveQuestions(questions);
             } else {
                 cout << "题目数量应在10-30之间" << endl;
             }
-        //*
         } catch (const exception& e) {
-            cout << "请输入有效的数字" << endl;
-        } 
-        //*/   
-        
+            cout << "请输入有效的数字或切换命令" << endl;
+        }
     }
     
-    // 主运行入口
+    // 保存题目到文件
+    void saveQuestionsToFile(const string& filepath, const vector<string>& questions) {
+        ofstream file(filepath);
+        if (file.is_open()) {
+            for (size_t i = 0; i < questions.size(); i++) {
+                file << (i + 1) << ". " << questions[i];
+                if (i < questions.size() - 1) file << "\n\n";  // 题目之间空一行
+            }
+            file.close();
+            cout << "题目已保存到: " << filepath << endl;
+        } else {
+            cout << "文件保存失败! 请检查目录权限。" << endl;
+        }
+    }
+
+public:
+    // 主运行循环：程序入口点
     void run() {
-        srand(time(nullptr));
+        srand(time(nullptr));  // 初始化随机数种子
+        
         cout << "=== 中小学数学卷子自动生成程序 ===" << endl;
         
         while (true) {
             if (!isLoggedIn) {
+                // 登录流程
                 cout << "请输入用户名和密码（用空格隔开）: ";
                 string username, password;
                 cin >> username >> password;
-                cin.ignore();
+                cin.ignore();  // 清除输入缓冲区
                 
                 if (login(username, password)) {
                     cout << "登录成功！当前选择为" << currentType << "出题" << endl;
@@ -555,18 +571,78 @@ public:
                 }
             }
             
+            // 登录后的主循环
             while (isLoggedIn) {
-                cout << endl << "准备生成" << currentType << "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）" << endl;
-                cout << "或者输入\"切换为小学/初中/高中\"来切换题目类型: ";
+                promptTypeAndCount();
                 processInput();
             }
         }
     }
+    
+    // 处理用户输入
+    void processInput() {
+        string input;
+        getline(cin, input);
+        input = trim(input);
+        
+        if (input == "-1") {
+            logout();  // 退出当前用户
+            return;
+        }
+        
+        if (input.find("切换为") == 0) {
+            string type = input.substr(9);
+            type = trim(type);
+            handleSwitchType(type);
+            return;
+        }
+        
+        processCountInput(input);
+    }
+    
+    // 处理数量输入或切换命令
+    void processCountInput(const string& input) {
+        string trimmedInput = trim(input);
+        
+        if (trimmedInput.find("切换为") == 0) {
+            string type = trimmedInput.substr(9);
+            type = trim(type);
+            handleSwitchType(type);
+            return;
+        }
+        
+        handleCountInput(trimmedInput);
+    }
+    
+    // 保存题目到文件（带时间戳的文件名）
+    void saveQuestions(const vector<string>& questions) {
+        time_t now = time(nullptr);
+        tm* localTime = localtime(&now);
+        
+        stringstream filename;
+        filename << setfill('0') 
+                << localTime->tm_year + 1900 << "-"
+                << setw(2) << localTime->tm_mon + 1 << "-"
+                << setw(2) << localTime->tm_mday << "-"
+                << setw(2) << localTime->tm_hour << "-"
+                << setw(2) << localTime->tm_min << "-"
+                << setw(2) << localTime->tm_sec << ".txt";
+                
+        string filepath = currentUser + "/" + filename.str();
+        saveQuestionsToFile(filepath, questions);
+    }
+    
+    // 注销当前用户
+    void logout() {
+        isLoggedIn = false;
+        currentUser = "";
+        currentType = "";
+    }
 };
 
+// 程序主函数：创建生成器实例并启动程序
 int main() {
-    
     MathPaperGenerator generator;
-    generator.run();
+    generator.run();  // 启动主循环
     return 0;
 }
\ No newline at end of file
diff --git a/src/main.exe b/src/main.exe
index f0dbc68..3fa63a3 100644
Binary files a/src/main.exe and b/src/main.exe differ
diff --git a/src/王五1/2025-09-29-19-09-07.txt b/src/王五1/2025-09-29-19-09-07.txt
new file mode 100644
index 0000000..e91e77c
--- /dev/null
+++ b/src/王五1/2025-09-29-19-09-07.txt
@@ -0,0 +1,59 @@
+1. (√77 + √72) - tan(30)
+
+2. (53² / 55 / sin(41) * √56 + 37²)
+
+3. tan(43) * 44
+
+4. (52² + √30) / tan(57)
+
+5. (√67 + cos(58) / 57) * 59
+
+6. cos(30) - 69
+
+7. tan(53) + √10
+
+8. √1 * sin(38)
+
+9. tan(24) + (35 + 40)
+
+10. sin(86) + 5
+
+11. cos(100) / (√63 + 41) * 63
+
+12. tan(48) * 100 - (90² + 16) * 39
+
+13. √31 - cos(75)
+
+14. (74 - 69) + tan(28)
+
+15. (89 + 12) + sin(1)
+
+16. 85² + cos(77) * (27 / √35 / 56)
+
+17. sin(72) - 54 * (70 + 77) - 25
+
+18. √49 / (√47 / cos(3) / 40)
+
+19. (57 / 7²) - cos(67)
+
+20. sin(11) / 63
+
+21. sin(47) * (50 - √24)
+
+22. tan(15) * 25
+
+23. 47 / cos(6)
+
+24. 3² / tan(39)
+
+25. (√12 / cos(19) + √29)
+
+26. sin(51) - (19 - √76) - 26
+
+27. (√84 + √95) + sin(26)
+
+28. sin(67) - 13
+
+29. cos(7) / 44 + (53 * √85)
+
+30. cos(4) / (46 / 13 / 85 * 25)
\ No newline at end of file