std::string UCTSearch::get_pv(BoardHistory& state, UCTNode& parent, bool use_san) {
if (!parent.has_children()) {
return std::string();
}
auto& best_child = parent.get_best_root_child(state.cur().side_to_move());
auto best_move = best_child.get_move();
auto res = use_san ? state.cur().move_to_san(best_move) : UCI::move(best_move);
StateInfo st;
state.cur().do_move(best_move, st);
auto next = get_pv(state, best_child, use_san);
if (!next.empty()) {
res.append(" ").append(next);
}
state.cur().undo_move(best_move);
return res;
}
std::string UCTSearch::get_pv(FastState & state, UCTNode& parent) {
if (!parent.has_children()) {
return std::string();
}
auto& best_child = parent.get_best_root_child(state.get_to_move());
if (best_child.first_visit()) {
return std::string();
}
auto best_move = best_child.get_move();
auto res = state.move_to_text(best_move);
state.play_move(best_move);
auto next = get_pv(state, best_child);
if (!next.empty()) {
res.append(" ").append(next);
}
return res;
}