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void choise30eur()
{
    client clients3;
    ofstream ofile;
    ofile.open("choise30eur.dat", ios::binary);
    cout << "_______________________________________________________________\n" << endl;
    cout << "You have chosen the subscription 'Standart' option for 30eur\n" << endl;
    cout << "Now please enter your full name,  Example: Aleksandr" << endl;
    cout << "_______________________________________________________________\n" << endl;
    cout << ">";
    cin >> clients3.name;
    ofile << clients3.name << endl;
    cout << "Now please enter your surname,  Example: Trofimov\n";
    cout << ">";
    cin >> clients3.surname;
    ofile << clients3.surname << endl;
    cout << "Enter your age,  Example:20" << endl;
    bool acceptable = false;
    while (!acceptable)
    {
        cin >> clients3.years;
        if (cin.fail())
        {
            cin.clear();
            cin.ignore(256, '\n');
            cerr << "\nERROR:You have chosen incorrect symbols\n" << endl;
            cout << "Try to enter your age again: ";
        }
        else
            cout << "Press ENTER to continue..." << endl;
            acceptable = true;
            _getch();
    }
        ofile << clients3.years << endl;
        ofile.close();
        _getch();
}