* @since 20.0
 */
@Beta
@DoNotMock
@ElementTypesAreNonnullByDefault
public final class GraphBuilder<N> extends AbstractGraphBuilder<N> {

  /** Creates a new instance with the specified edge directionality. */
  private GraphBuilder(boolean directed) {
    super(directed);
  }

  /** Returns a {@link GraphBuilder} for building directed graphs. */
  public static GraphBuilder<Object> directed() {

  boolean allowsParallelEdges = false;
  ElementOrder<? super E> edgeOrder = ElementOrder.insertion();
  Optional<Integer> expectedEdgeCount = Optional.absent();

  /** Creates a new instance with the specified edge directionality. */
  private NetworkBuilder(boolean directed) {
    super(directed);
  }

  /** Returns a {@link NetworkBuilder} for building directed networks. */
  public static NetworkBuilder<Object, Object> directed() {

 * @since 20.0
 */
@Beta
@ElementTypesAreNonnullByDefault
public final class ValueGraphBuilder<N, V> extends AbstractGraphBuilder<N> {

  /** Creates a new instance with the specified edge directionality. */
  private ValueGraphBuilder(boolean directed) {
    super(directed);
  }

  /** Returns a {@link ValueGraphBuilder} for building directed graphs. */
  public static ValueGraphBuilder<Object, Object> directed() {

  boolean allowsParallelEdges = false;
  ElementOrder<? super E> edgeOrder = ElementOrder.insertion();
  Optional<Integer> expectedEdgeCount = Optional.absent();

  /** Creates a new instance with the specified edge directionality. */
  private NetworkBuilder(boolean directed) {
    super(directed);
  }

  /** Returns a {@link NetworkBuilder} for building directed networks. */
  public static NetworkBuilder<Object, Object> directed() {

    }
    return hasEdgeConnecting(endpoints.nodeU(), endpoints.nodeV());
  }

  /**
   * Throws an IllegalArgumentException if the ordering of {@code endpoints} is not compatible with
   * the directionality of this graph.
   */
  protected final void validateEndpoints(EndpointPair<?> endpoints) {
    checkNotNull(endpoints);
    checkArgument(isOrderingCompatible(endpoints), ENDPOINTS_MISMATCH);
  }

    }
    return hasEdgeConnecting(endpoints.nodeU(), endpoints.nodeV());
  }

  /**
   * Throws an IllegalArgumentException if the ordering of {@code endpoints} is not compatible with
   * the directionality of this graph.
   */
  protected final void validateEndpoints(EndpointPair<?> endpoints) {
    checkNotNull(endpoints);
    checkArgument(isOrderingCompatible(endpoints), ENDPOINTS_MISMATCH);
  }

// The methods of an Ordering should only be called by one goroutine at a time.
type Ordering struct {
	runes      [][]rune
	directions []Direction
	startpos   []int
}

// Direction reports the directionality of the runs.
//
// The direction may be LeftToRight, RightToLeft, Mixed, or Neutral.
func (o *Ordering) Direction() Direction {
	return o.directions[0]
}

// NumRuns returns the number of runs.

				// inexactly unifying channel type remains assignable (go.dev/issue/62157).
				//
				// If we have multiple defined channel types, they are either identical or we
				// have assignment conflicts, so we can ignore directionality in this case.
				//
				// If we have defined and literal channel types, a defined type wins to avoid
				// order dependencies.
				if mode&exact == 0 {
					switch {
					case xn:

//  - levels array over line
//  - reordering array over line
//
// Note that for conformance to the Unicode Bidirectional Algorithm,
// implementations are only required to generate correct reordering and
// character directionality (odd or even levels) over a line. Generating
// identical level arrays over a line is not required. Bidi explicit format
// codes (LRE, RLE, LRO, RLO, PDF) and BN can be assigned arbitrary levels and

				// inexactly unifying channel type remains assignable (go.dev/issue/62157).
				//
				// If we have multiple defined channel types, they are either identical or we
				// have assignment conflicts, so we can ignore directionality in this case.
				//
				// If we have defined and literal channel types, a defined type wins to avoid
				// order dependencies.
				if mode&exact == 0 {
					switch {
					case xn: