exam oop

#include <iostream>
#include <string>
#include <fstream>
#include <Windows.h>

using namespace std;

void sleep(int rarely_used);

class CPerson
{
private:
    string name;
    string EGN;

public:
    CPerson()
    {
        name = "Lucian";
        EGN = "8904162244";
    }

    CPerson(string name, string EGN)
    {
        this -> name = name;
        this -> EGN = EGN;
    }

    string get_name()
    {
        return name;
    }

    string get_EGN()
    {
        return EGN;
    }

    void overwrite_name(string name)
    {
        this -> name = name;
    }

    void overwrite_EGN(string EGN)
    {
        this -> EGN = EGN;
    }

    void getYMD(const string& strEGN,int &iYear,int &iMonth, int &iDay)const
    {
        iYear = stoi(strEGN.substr(0,2));
        if(iYear < 18) iYear+=2000;
        else iYear+=1900;
        iMonth = stoi(strEGN.substr(2,2));
        iDay = stoi(strEGN.substr(4,2));
    }

    int get_age()
    {
        return 2017-stoi(EGN.substr(0,2));
    }

        bool isValid(const string& strEGN)
    {
            int d = strEGN[strEGN.length()-1]-'0';
            int weight[9] = {2,4,8,5,10,9,7,3,6};
            int res = 0;
            for(int i=0; i < strEGN.length()-1; i++)
                res+= (strEGN[i]-'0')*weight[i];
            if(res%11 < 10) res%=11;
            else res = 0;
            if(d == res) return true;

        return false;
    }

    friend ostream& operator<<(ostream& toStream, const CPerson& pers);
    friend istream& operator>>(istream& fromStream, CPerson& pers);
};

ostream& operator<<(ostream& toStream, const CPerson& pers)
{
    if(&toStream==&cout)
    {
        cout << "\tObject of class CPerson: ";
        toStream << "\nName: " << pers.name;
        toStream << "\nEGN: " << pers.EGN;
    }
    else
    {
        toStream << pers.name << endl;
        toStream << pers.EGN << endl;
    }
    return toStream;
}

istream& operator>>(istream& fromStream, CPerson& pers)
{
    bool p = false;
    if(&fromStream==&cin)
    {
        cout << "\nEnter name: ";
    }
    fromStream >> pers.name;
    //getline(fromStream,per.name);
    do
    {
        if(&fromStream==&cin) cout << "Enter EGN: ";
        fromStream >> pers.EGN;
        if(pers.isValid(pers.EGN)) p = true;
        if(!p) cout << "Invalid EGN! " << endl;
    }while(pers.EGN.length()!=10 || pers.EGN.find_first_of("0123456789") || !p);
    //getline(fromStream,per.EGN);
    return fromStream;
}

class CAddress
{
private:
    string street;
    string code;
    string city;

public:
    CAddress()
    {
        street = "Angel Kunchev #15";
        code = "9000";
        city = "Varna";
    }

    CAddress(string street, string code, string city)
    {
        this -> street = street;
        this -> code = code;
        this -> city = city;
    }

    CAddress(const CAddress& x)
    {
        street = x.street;
        code = x.code;
        city = x.city;
    }

    string get_street()
    {
        return street;
    }

    string get_code()
    {
        return code;
    }

    string get_city()
    {
        return city;
    }

    ostream& Output(ostream& toStream) const
    {
        if(&toStream == &cout)
        {
            toStream << "\ncity: " << city;
            toStream << "\nstreet: " << street;
            toStream << "\ncode: " << code;
        }

        else
        {
            toStream << city << endl;
            toStream << street << endl;
            toStream << code << endl;
        }
        return toStream;
    }

    friend ostream& operator<<(ostream& toStream, const CAddress& addr);
    friend istream& operator>>(istream& fromStream, CAddress& addr);
};

ostream& operator<<(ostream& toStream, const CAddress& addr)  // !!!!
{
    if(&toStream==&cout)
    {
        toStream << "\nCity name: " << addr.city;
        toStream << "\nStreet name: " << addr.street;
        toStream << "\nCode: " << addr.code;
    }
    else
    {
        toStream << addr.city << endl;
        toStream << addr.street << endl;
        toStream << addr.code << endl;
    }
    return toStream;
}

istream& operator>>(istream& fromStream, CAddress& addr)
{
    if(&fromStream==&cin)
    {
        cout << "Enter city name: ";
    }
    fromStream >> addr.city;
    if(&fromStream==&cin) cout << "Enter street name: ";
    fromStream >> addr.street;
    if(&fromStream==&cin) cout << "Enter city's code: ";
    fromStream >> addr.code;
    return fromStream;
}

class CGSM
{
private:
    string model;
    double tariff_plan;
public:
    CGSM()
    {
        model = "Samsung Galaxy";
        tariff_plan = 14.99;
    }

    CGSM(string model, double tariff_plan)
    {
        this -> model = model;
        this -> tariff_plan = tariff_plan;
    }

    string get_model() { return model; }
    double get_tariff_plan() { return tariff_plan; }
    void set_model(string model) { this -> model = model; }
    void set_tariff_plain(double tariff_plan) { this -> tariff_plan = tariff_plan; }
    virtual ostream& OutputGSM(ostream& toStream) = 0;
    virtual string getGSMNumber() const = 0;
    virtual istream& InputGSM(istream& fromStream) = 0;
};

class CStudent : public CPerson, public CGSM
{
private:
    string FN;
    friend class CAddress;
    CAddress *a; // !!
    string phone;
public:
    CStudent()
    {
        FN = "61662115";
        a = new CAddress();
        phone = "0892467472";
    }

    CStudent(string name, string EGN, string street, string code, string city, string phone, string model, double tariff_plan):CPerson(name, EGN),CGSM(model, tariff_plan)
    {
        FN = "61662115";
        this -> phone = phone;
        a = new CAddress(street, code, city);
    }
    CStudent(string name, string EGN, string phone, string model, double tariff_plan, CAddress* a):CPerson(name,EGN),CGSM(model,tariff_plan)
    {
        FN = "61662115";
        this -> phone = phone;
        this->a = new CAddress(a->get_street(),a->get_code(),a->get_city());
    }
    CStudent(string name, string EGN, string FN, string street, string code, string city, string phone, string model, double tariff_plan):CPerson(name, EGN),CGSM(model, tariff_plan)
    {
        this -> FN = FN;
        this -> phone = phone;
        a = new CAddress(street, code, city);
    }

    CStudent(CStudent& obj1):CPerson(obj1.get_name(),obj1.get_EGN()),CGSM(obj1.get_model(),obj1.get_tariff_plan())
    {
        FN = obj1.FN;
        a = obj1.a;
    }

    CStudent(CStudent& x, int unused)
    {
        *a = *x.a;
    }
    ~CStudent()
    {
            a = NULL;
            delete[] a;
    }

    string get_street()
    {
        return (*a).get_street();
    }

    string get_FN()
    {
        return FN;
    }

    string get_code()
    {
        return (*a).get_code();
    }

    string get_city()
    {
        return (*a).get_city();
    }

    ostream& Output(ostream& toStream)
    {
        if(&toStream == &cout)
        {
            toStream << "Name: " << get_name();
            toStream << "\nEGN: " << get_EGN();
            toStream << "\nFN: " << FN;
            (*a).Output(toStream);
            toStream << "\nPhone number: " << phone;
            toStream << "\nModel: " << get_model();
            toStream << "\nTariff plan: " << get_tariff_plan();
        }

        else
        {
            toStream << get_name() << endl;
            toStream << get_EGN() << endl;
            toStream << FN << endl;
            (*a).Output(toStream);
            toStream << phone << endl;
            toStream << get_model() << endl;
            toStream << get_tariff_plan() << endl;
        }

        return toStream;
    }

    void overwrite()
    {
        string name,street, code, city, EGN;
        cout << "\n\t\tOverwrite function ";
        cout << "\nEnter the new name: ";
        getline(cin,name);
        cout << "Enter the new EGN: ";
        getline(cin, EGN);
        cout << "Enter the FN: ";
        getline(cin, FN);
        cout << "\tEnter the new address ";
        cout << "\nStreet name: ";
        getline(cin, street);
        cout << "\nZip code: ";
        getline(cin, code);
        cout << "\nCity: ";
        getline(cin, city);
        a = new CAddress(street, code, city);
        CPerson::overwrite_name(name);
        CPerson::overwrite_EGN(EGN);
    }

    ostream& OutputGSM(ostream& toStream)
    {
        if(&toStream == &cout)
        {
            toStream << "\nModel: " << get_model();
            toStream << "\nTelephone number: " << phone;
            toStream << "\nTariff plan: " << get_tariff_plan();
        }
        else
        {
            toStream << get_model() << endl;
            toStream << phone << endl;
            toStream << get_tariff_plan() << endl;
        }
        return toStream;
    }

    string getGSMNumber() const
    {
        return phone;
    }

    istream& InputGSM(istream& fromStream)
    {
        if(&fromStream==&cin)
            cout << "\nEnter new telephone number: ";
        fromStream >> phone;
        return fromStream;
    }

    bool operator>(CStudent& studR)
    {
        return get_tariff_plan() > studR.get_tariff_plan();
    }

    friend void ConsoleInputEGN(CStudent& stud);
    friend ostream& operator<<(ostream& toStream, CStudent& stud);
    friend bool operator ==(CStudent& stud1, CStudent& stud2);
    friend bool operator !=(CStudent& stud1, CStudent& stud2);
    friend bool operator <(CStudent& stud1, CStudent& stud2);
    friend bool operator >=(CStudent& stud1, CStudent& stud2);
    friend istream& operator>>(istream& fromStream, CStudent& stud);
};


void ConsoleInputEGN(CStudent& stud)
{
    string EGN;
    cout << "\nEnter EGN: ";
    getline(cin,EGN);
    stud.overwrite_EGN(EGN);
}

ostream& operator<<(ostream& toStream, CStudent& stud)
{
    if(&toStream==&cout)
    {
        toStream << "\tObject of class CStudent: ";
        toStream << "\nName: " << stud.get_name();
        toStream << "\nEGN: " << stud.get_EGN();
        toStream << "\nFN: " << stud.FN;
        toStream << "\nPhone number: " << stud.phone;
    }
    else
    {
        toStream << stud.get_name() << endl;
        toStream << stud.get_EGN() << endl;
        toStream << stud.FN << endl;
        toStream << stud.phone << endl;
    }
    toStream << *stud.a;
    return toStream;
}

istream& operator>>(istream& fromStream, CStudent& stud)
{
    CPerson per;
    cin >> per;
    stud.CPerson::CPerson(per);
    CAddress p;
    cin.ignore();
    cin >> p;
    *stud.a = p;
    if(&fromStream==&cin)
    {
        cout << "Enter FN: ";
    }
    cin.seekg(0,ios::end);
    cin.clear();
    string s;
    double c;
    getline(fromStream,stud.FN);
    if(&fromStream==&cin)
        { cout << "Enter phone's model: "; }
    fromStream >> s;
        stud.set_model(s);
    if(&fromStream==&cin)
       { cout << "Enter phone's number: "; }
       fromStream >> stud.phone;
    if(&fromStream==&cin)
        { cout << "Enter phone's tariff: "; }
    fromStream >> c;
    stud.set_tariff_plain(c);

    return fromStream;
}

bool operator ==( CStudent& stud1, CStudent& stud2)
{
    return stud1.get_age() == stud2.get_age();
}

bool operator !=(CStudent& stud1, CStudent& stud2)
{
    return stud1.get_age() != stud2.get_age();
}

bool operator <(CStudent& stud1, CStudent& stud2)
{
    return stud1.get_age() < stud2.get_age();
}

bool operator >=(CStudent& stud1, CStudent& stud2)
{
    return stud1.get_age() >= stud2.get_age();
}

void main()
{
    CPerson *p = new CPerson;
    CAddress *a = new CAddress;
    CStudent *s1 = new CStudent;
    cout << "Enter values for the object of class CPerson: ";
    cin >> *p;
    sleep(-2000);
    cout << "Enter values for the object of class CAddress: " << endl;
    cin >> *a;
    sleep(-2000);

    cout << "Object of class CStudent: " << endl;
    cin >> *s1;
    sleep(-2000);

    cout << *p;
    sleep(1000);
    cout << "Object of class CAddress: ";
    (*a).Output(cout);
    sleep(2500);
    cout << *s1;
    sleep(4000);
    CStudent *s2 = new CStudent("Rabia", "9708271063", "0892467472", "Samsung", 13.05, a);
    (*s2).Output(cout);
    sleep(4000);

    cout << "Output GSM function for s1: " << endl;
    (*s1).OutputGSM(cout);
    sleep(1500);
    cout << "InputGSM function for s2: " << endl;
    (*s2).InputGSM(cin);
    cout << "\nResult from Get GSM number function for s2: " << (*s2).getGSMNumber();
    sleep(0);

    if(*s1 > *s2) cout << "\t\t\t\ts1 > s2 ";
    else cout << "\t\t\t\ts1 <= s2 ";
    sleep(1000);

    delete p;
    delete a;
    delete s1;
    delete s2;

    CStudent *s = new CStudent[20];
    fstream oFile;
    oFile.open("Tema04.txt", ios::in);
    if(!oFile)
    {
        cout << "File cannot be opened!";
        exit(1);
    }
    int i = 0;
    while(!oFile.eof()) // while(oFile.good())
    {
        oFile >> *(s+i);
        i++;
    }
    oFile.close();

    cout << endl;
    system("pause");
}

void sleep(int rarely_used)
{
    Sleep(3000+rarely_used);
    system("cls");
}