Binary overload inheritance?

Question

OOP

Hello, I need to cast a parent class to a child class in order to use the overloaded child class operator. The overloaded operator itself is defined as a friend function because it takes two values.
pointClass[0] - a pointer that is initialized as a base class

void SplitString(int choice)
{
    char string[100];

    system("clear");
    cout << "Введите значение второго операнда" << endl;
    cin >> string;

    Str_Indef strIndef(string);

    strIndef = strIndef + (Str_Indef)*pointClass[0]; // Так  я привожу и  не  работает

    strIndef.Print();
    Pause();
}

Overload code.

const Str_Indef operator +(const Str_Indef& right, const Str_Indef& left)
{
    std::cout << "ПЕРЕГРУЗКА ОПЕРАЦИИ + [Строка-Идетификатор]" << std::endl;
    char *pointerChar = new char[right.size + left.size-1];

    strcpy(pointerChar, left.p_char);
    strcat(pointerChar, right.p_char);

    Str_Indef returnString;

    returnString.p_char = pointerChar;
    returnString.size = strlen(pointerChar);

    return returnString;
};

The overload itself is implemented as a friend function, and as you know, they cannot be virtual, which does not allow them to be inherited.

Answer 1

dynamic_cast, static_cast, reinterpret_cast