Parking Lot

#include <iostream>
#include <vector>
#include <set>
#include <string>
#include <sstream>  // std::istringstream
#include <algorithm> // std::find

using namespace std;

int main()
{
    vector<string> carNumber;
    string input;
    string direction;
    string number;

    vector<string>::iterator it;
    while (true)
    {
        getline(cin, input);
        if (input == "END")
            break;
        istringstream istr(input);
        istr >> direction;
        istr >> number;
        if (direction == "IN,")
            carNumber.push_back(number);
        else if(carNumber.size() > 0)
        {


            it = find(carNumber.begin(), carNumber.end(), number);
            if (it != carNumber.end())
                carNumber.erase(it);

        }

    }

    if (carNumber.empty())
        cout << "Parking Lot is Empty" << endl;
    else
        for (string elm : carNumber)
            cout << elm << endl;


}