* {@code Supplier}, whose elements are the result of applying {@code elementFunction} to the
   * inputs, with counts equal to the result of applying {@code countFunction} to the inputs.
   * Elements are added in encounter order.
   *
   * <p>If the mapped elements contain duplicates (according to {@link Object#equals}), the element
   * will be added more than once, with the count summed over all appearances of the element.
   *

    Counter c2 = new Counter(aa);
    Thread t1 = newStartedThread(c1);
    Thread t2 = newStartedThread(c2);
    awaitTermination(t1);
    awaitTermination(t2);
    assertEquals(SIZE * COUNTDOWN, c1.counts + c2.counts);
  }

  /** a deserialized serialized array holds same values */
  public void testSerialization() throws Exception {
    AtomicDoubleArray x = new AtomicDoubleArray(SIZE);

    Counter c2 = new Counter(aa);
    Thread t1 = newStartedThread(c1);
    Thread t2 = newStartedThread(c2);
    awaitTermination(t1);
    awaitTermination(t2);
    assertEquals(SIZE * COUNTDOWN, c1.counts + c2.counts);
  }

  /** a deserialized serialized array holds same values */
  public void testSerialization() throws Exception {
    AtomicDoubleArray x = new AtomicDoubleArray(SIZE);

public abstract class MultimapBuilder<K0 extends @Nullable Object, V0 extends @Nullable Object> {
  /*
   * Leaving K and V as upper bounds rather than the actual key and value types allows type
   * parameters to be left implicit more often. CacheBuilder uses the same technique.
   */

  private MultimapBuilder() {}

  private static final int DEFAULT_EXPECTED_KEYS = 8;

  /** Uses a hash table to map keys to value collections. */

    for (auto it : op_it->second.input_tensor_id) {
      auto count_it = result.tensor_usage_counts.find(it);
      if (count_it != result.tensor_usage_counts.end()) {
        count_it->second++;
      } else {
        result.tensor_usage_counts[it] = 1;
        if (tensor_tape.find(it) != tensor_tape.end()) {
          tensor_stack.push_back(it);
        }
      }
    }

  private static boolean isPermutation(List<?> first, List<?> second) {
    if (first.size() != second.size()) {
      return false;
    }
    ObjectCountHashMap<?> firstCounts = counts(first);
    ObjectCountHashMap<?> secondCounts = counts(second);
    if (first.size() != second.size()) {
      return false;
    }
    for (int i = 0; i < first.size(); i++) {

    }
    int div = p / q;
    int rem = p - q * div; // equal to p % q

    if (rem == 0) {
      return div;
    }

    /*
     * Normal Java division rounds towards 0, consistently with RoundingMode.DOWN. We just have to
     * deal with the cases where rounding towards 0 is wrong, which typically depends on the sign of
     * p / q.
     *

  }

  private static <D extends GenericDeclaration> TypeVariable<D> withBounds(
      TypeVariable<D> typeVariable, Type... bounds) {
    return Types.newArtificialTypeVariable(
        typeVariable.getGenericDeclaration(), typeVariable.getName(), bounds);
  }

  private static class TypeVariableEqualsTester {
    private final EqualsTester tester = new EqualsTester();

  }

  private static <D extends GenericDeclaration> TypeVariable<D> withBounds(
      TypeVariable<D> typeVariable, Type... bounds) {
    return Types.newArtificialTypeVariable(
        typeVariable.getGenericDeclaration(), typeVariable.getName(), bounds);
  }

  private static class TypeVariableEqualsTester {
    private final EqualsTester tester = new EqualsTester();

    EnumSet<SomeEnum> noUnits = Sets.complementOf(allUnits, SomeEnum.class);
    verifySetContents(noUnits, EnumSet.noneOf(SomeEnum.class));
  }

  @J2ktIncompatible
  @GwtIncompatible // complementOf
  public void testComplementOfEmptyEnumSetWithoutType() {
    Set<SomeEnum> noUnits = EnumSet.noneOf(SomeEnum.class);
    EnumSet<SomeEnum> allUnits = Sets.complementOf(noUnits);