Check hidden city

void main() {
    string choiceAdv = "choiceAdventure787";
    int previousChoice = to_int(get_property(choiceAdv));
    location whereToCheck = $location[An Overgrown Shrine (Southeast)];

    if (previousChoice != 6) {
        set_property(choiceAdv, 6);
    }

    adv1(whereToCheck, -1, "");

    if (to_int(get_property(choiceAdv)) != previousChoice) {
        set_property(choiceAdv, previousChoice);
    }
}