/** Opened states are states that still contains todo actors.
* When backtracking, we pick a state from it*/
std::vector<std::shared_ptr<State>> opened_states_;
std::shared_ptr<State> best_opened_state();
/** Opened states are states that still contains todo actors.
* When backtracking, we pick a state from it*/
std::vector<std::shared_ptr<State>> opened_states_;
std::shared_ptr<State> best_opened_state();