return crc1
	}

	even := make([]uint64, 32) // even-power-of-two zeros operator
	odd := make([]uint64, 32)  // odd-power-of-two zeros operator

	// put operator for one zero bit in odd
	odd[0] = uint64(poly) // CRC-32 polynomial
	row := uint64(1)
	for n := 1; n < 32; n++ {
		odd[n] = row
		row <<= 1
	}

	// put operator for two zero bits in even
	gf2MatrixSquare(even, odd)

          2 * THREE_BYTE_ROUNDTRIPPABLE_CHARACTERS * ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS
          +
          // Two two byte characters
          TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS * TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS
          +
          // Permutations of one and two byte characters
          3
              * TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS
              * ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS

  /**
   * Compares two objects using a comparator, <i>if</i> the result of this comparison chain has not
   * already been determined.
   */
  public abstract <T extends @Nullable Object> ComparisonChain compare(
      @ParametricNullness T left, @ParametricNullness T right, Comparator<T> comparator);

  /**

import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@code AbstractBiMap}.
 *
 * @author Mike Bostock
 */
@NullUnmarked
public class AbstractBiMapTest extends TestCase {

  // The next two tests verify that map entries are not accessed after they're
  // removed, since IdentityHashMap throws an exception when that occurs.
  @SuppressWarnings("IdentityHashMapBoxing") // explicitly testing IdentityHashMap

import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@code AbstractBiMap}.
 *
 * @author Mike Bostock
 */
@NullUnmarked
public class AbstractBiMapTest extends TestCase {

  // The next two tests verify that map entries are not accessed after they're
  // removed, since IdentityHashMap throws an exception when that occurs.
  @SuppressWarnings("IdentityHashMapBoxing") // explicitly testing IdentityHashMap

    public boolean atMost(final DialectVersion v) {
        return ordinal() <= v.ordinal();
    }

    /**
     * Get the minimum of two dialect versions
     *
     * @param a the first version to compare
     * @param b the second version to compare
     * @return smaller of the two versions
     */
    public static DialectVersion min(final DialectVersion a, final DialectVersion b) {
        if (a.atMost(b)) {

    unfiltered.put("two", 2);
    unfiltered.put("three", 3);
    unfiltered.put("four", 4);
    assertEquals(ImmutableMap.of("two", 2, "three", 3, "four", 4), unfiltered);
    assertEquals(ImmutableMap.of("three", 3, "four", 4), filtered);

    unfiltered.remove("three");
    assertEquals(ImmutableMap.of("two", 2, "four", 4), unfiltered);
    assertEquals(ImmutableMap.of("four", 4), filtered);

    assertEquals(s2, three.next().target);
    assertEquals(o1, three.next().target);
    assertFalse(three.hasNext());

    Iterator<Subscriber> two = registry.getSubscribers("");
    assertEquals(s1, two.next().target);
    assertEquals(o1, two.next().target);
    assertFalse(two.hasNext());
  }

  public static class StringSubscriber {

    @Subscribe
    public void handle(String s) {}
  }

    Object one = new Object();
    Object two = new Object();
    Object three = new Object();
    Object four = new Object();
    Object five = new Object();
    Object six = new Object();

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);

    Object one = new Object();
    Object two = new Object();
    Object three = new Object();
    Object four = new Object();
    Object five = new Object();
    Object six = new Object();

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    map.put(two, three);
    map.remove(two, three);