файлове

#include<iostream>
#include<string>
#include<fstream>

const char FILE_NAME[] = "file.txt";

class Entity {
    std::string name;
    size_t id;
    std::string password;
public:
    Entity() { name = ""; id = 0; password = ""; }
    Entity(const std::string& _name, size_t id, const std::string& _pass) { name = _name; this->id = id; password = _pass; }

    std::string getPass() const { return this->password; }

    std::string getName() const { return this->name; }

    size_t getID() const { return this->id; }

    ~Entity() { };
};

void saveEntityToFile(const char* location, const Entity& toSave) {
    std::ofstream outFile(location, std::ios::app);

    if (outFile.bad())
        return;

    outFile << toSave.getName() << " " << toSave.getID() << " " << toSave.getPass() << '\n';

    outFile.close();
}

Entity readEntityFromFile(const char* location) {
    std::ifstream inFile(location);
    if (inFile.bad())
        return Entity();

    std::string nName;
    std::string nPass;
    size_t ID;

    inFile >> nName >> ID >> nPass;

    inFile.close();

    return Entity(nName, ID, nPass);
}

int main() {
    Entity test("Entity1", 1234, "Password");
    saveEntityToFile(FILE_NAME, test);
    Entity readedEntity = readEntityFromFile(FILE_NAME);
    std::cout << readedEntity.getName() << " " << readedEntity.getID() << " " << readedEntity.getPass() << '\n';
}