class CarsRegister
{
private:
    static vector<Person*> personsByName[26];
/////
    static void clearPersonsByName()
    {
        for (int i = 0; i < 26; i++)
        {
            while (!personsByName[i].empty())
            {
                personsByName[i].erase(personsByName[i].end()-1);
            }

            personsByName[i].clear();
        }
    }

/////
    static void addPersonToNamesList(Person * person)
    {
        int start_letter_index = (int)(tolower(person->getName()[0])) - 97;
        if (start_letter_index >= 0 && start_letter_index <= 25)
        {
           personsByName[start_letter_index].push_back(person);
        }
        else
        {
            throw "Invalid person name detected (no first letter)";
        }
    }
//////
public:

    static string listAllPersonsByFirstNameLetter(const char & letter)
    {
        ostringstream str;

        int start_letter_index = (int)(tolower(letter)) - 97;
        if (start_letter_index >= 0 && start_letter_index <= 25)
        {
            for (int i = 0; i < personsByName[start_letter_index].size(); i++)
            {
                str << ".............................."
                    << endl << personsByName[start_letter_index][i]->getInfo();
            }
        }
        else
        {
            throw "Invalid symbol instead of a letter";
        }

        str << endl;

        return str.str();
    }

    static string listPersonsSummaryByNameStartingLetter()
    {
        ostringstream str;

        for (int i = 0; i < 26; i++)
        {
            str << (char)(i+65) << " : " << personsByName[i].size() << endl;
        }

        str << endl;

        return str.str();
    }
}

////

vector<Person*> CarsRegister::personsByName[26]{};

////