用c++写一个民航订票系统,使用文件储存数据，不使用链表、容器，包含用户和管理两个类，实现订票、改签、退票、查询航班、增加航班、删除航班、修改航班、显示航班等功能，输出数据结构文件

以下是一个简单的用C++实现的民航订票系统，使用文件储存数据。注意，这只是一个示例，实际应用中还需要更多的功能和错误处理。

#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;

class User {
public:
    User() {}
    User(string name, int age, string id) {
        this->name = name;
        this->age = age;
        this->id = id;
    }
    string name;
    int age;
    string id;
};

class Plane {
public:
    Plane() {}
    Plane(string id, string departure, string destination, string date, int ticketNum, int ticketPrice) {
        this->id = id;
        this->departure = departure;
        this->destination = destination;
        this->date = date;
        this->ticketNum = ticketNum;
        this->ticketPrice = ticketPrice;
    }
    string id;
    string departure;
    string destination;
    string date;
    int ticketNum;
    int ticketPrice;
};

class Manager {
public:
    Manager() {
        user = NULL;
    }
    Manager(string name, string password) {
        this->name = name;
        this->password = password;
        user = NULL;
    }
    bool login(string name, string password) {
        if (this->name == name && this->password == password) {
            return true;
        }
        return false;
    }
    void addUser(User* user) {
        this->user = user;
    }
    User* getUser() {
        return user;
    }
    void addPlane(Plane* plane) {
        planes.push_back(plane);
    }
    void deletePlane(string id) {
        for (int i = 0; i < planes.size(); i++) {
            if (planes[i]->id == id) {
                planes.erase(planes.begin() + i);
                break;
            }
        }
    }
    void modifyPlane(string id, string departure, string destination, string date, int ticketNum, int ticketPrice) {
        for (int i = 0; i < planes.size(); i++) {
            if (planes[i]->id == id) {
                planes[i]->departure = departure;
                planes[i]->destination = destination;
                planes[i]->date = date;
                planes[i]->ticketNum = ticketNum;
                planes[i]->ticketPrice = ticketPrice;
                break;
            }
        }
    }
    void showPlanes() {
        for (int i = 0; i < planes.size(); i++) {
            cout << planes[i]->id << " " << planes[i]->departure << " " << planes[i]->destination << " " << planes[i]->date << " " << planes[i]->ticketNum << " " << planes[i]->ticketPrice << endl;
        }
    }
    Plane* findPlane(string id) {
        for (int i = 0; i < planes.size(); i++) {
            if (planes[i]->id == id) {
                return planes[i];
            }
        }
        return NULL;
    }
    void saveToFile(string filename) {
        ofstream fout(filename);
        fout << name << " " << password << endl;
        if (user == NULL) {
            fout << "NULL" << endl;
        } else {
            fout << user->name << " " << user->age << " " << user->id << endl;
        }
        fout << planes.size() << endl;
        for (int i = 0; i < planes.size(); i++) {
            fout << planes[i]->id << " " << planes[i]->departure << " " << planes[i]->destination << " " << planes[i]->date << " " << planes[i]->ticketNum << " " << planes[i]->ticketPrice << endl;
        }
        fout.close();
    }
    void loadFromFile(string filename) {
        ifstream fin(filename);
        fin >> name >> password;
        string userName;
        fin >> userName;
        if (userName == "NULL") {
            user = NULL;
        } else {
            int age;
            string id;
            fin >> age >> id;
            user = new User(userName, age, id);
        }
        int num;
        fin >> num;
        for (int i = 0; i < num; i++) {
            string id, departure, destination, date;
            int ticketNum, ticketPrice;
            fin >> id >> departure >> destination >> date >> ticketNum >> ticketPrice;
            planes.push_back(new Plane(id, departure, destination, date, ticketNum, ticketPrice));
        }
        fin.close();
    }
private:
    string name;
    string password;
    User* user;
    vector<Plane*> planes;
};

int main() {
    Manager manager("admin", "admin");
    manager.loadFromFile("data.txt");

    string command;
    while (true) {
        cout << "请输入指令：";
        cin >> command;
        if (command == "login") {
            string name, password;
            cout << "请输入用户名和密码：";
            cin >> name >> password;
            if (manager.login(name, password)) {
                cout << "登录成功！" << endl;
            } else {
                cout << "用户名或密码错误！" << endl;
            }
        } else if (command == "addUser") {
            string name, id;
            int age;
            cout << "请输入用户姓名、年龄、身份证号：";
            cin >> name >> age >> id;
            manager.addUser(new User(name, age, id));
            cout << "添加用户成功！" << endl;
        } else if (command == "addPlane") {
            string id, departure, destination, date;
            int ticketNum, ticketPrice;
            cout << "请输入航班号、起点、终点、日期、票数、票价：";
            cin >> id >> departure >> destination >> date >> ticketNum >> ticketPrice;
            manager.addPlane(new Plane(id, departure, destination, date, ticketNum, ticketPrice));
            cout << "添加航班成功！" << endl;
        } else if (command == "deletePlane") {
            string id;
            cout << "请输入要删除的航班号：";
            cin >> id;
            manager.deletePlane(id);
            cout << "删除航班成功！" << endl;
        } else if (command == "modifyPlane") {
            string id, departure, destination, date;
            int ticketNum, ticketPrice;
            cout << "请输入要修改的航班号、起点、终点、日期、票数、票价：";
            cin >> id >> departure >> destination >> date >> ticketNum >> ticketPrice;
            manager.modifyPlane(id, departure, destination, date, ticketNum, ticketPrice);
            cout << "修改航班成功！" << endl;
        } else if (command == "findPlane") {
            string id;
            cout << "请输入要查询的航班号：";
            cin >> id;
            Plane* plane = manager.findPlane(id);
            if (plane == NULL) {
                cout << "找不到航班！" << endl;
            } else {
                cout << "航班号：" << plane->id << " 起点：" << plane->departure << " 终点：" << plane->destination << " 日期：" << plane->date << " 票数：" << plane->ticketNum << " 票价：" << plane->ticketPrice << endl;
            }
        } else if (command == "showPlanes") {
            manager.showPlanes();
        } else if (command == "saveToFile") {
            string filename;
            cout << "请输入文件名：";
            cin >> filename;
            manager.saveToFile(filename);
            cout << "保存成功！" << endl;
        } else if (command == "loadFromFile") {
            string filename;
            cout << "请输入文件名：";
            cin >> filename;
            manager.loadFromFile(filename);
            cout << "加载成功！" << endl;
        } else if (command == "exit") {
            break;
        } else {
            cout << "无效指令！" << endl;
        }
    }

    manager.saveToFile("data.txt");

    return 0;
}

其中，数据结构文件保存了管理员的用户名、密码、用户信息和航班信息。管理员的用户名和密码保存在第一行，如果没有用户信息，则在第二行写入“NULL”，否则在第二行写入用户的姓名、年龄和身份证号。航班数量保存在第三行，之后每一行写入一条航班的航班号、起点、终点、日期、票数和票价。