}

  static class MeanAndVariance {
    private final double mean;
    private final double variance;

    MeanAndVariance(double mean, double variance) {
      this.mean = mean;
      this.variance = variance;
    }

    @Override
    public int hashCode() {
      return Double.hashCode(mean) * 31 + Double.hashCode(variance);
    }
  }

  enum VarianceAlgorithm {
    DO_NOT_COMPUTE {
      @Override

  public void testElapsed_notRunning() {
    ticker.advance(1);
    stopwatch.start();
    ticker.advance(4);
    stopwatch.stop();
    ticker.advance(9);
    assertEquals(4, stopwatch.elapsed(NANOSECONDS));
  }

  public void testElapsed_multipleSegments() {
    stopwatch.start();
    ticker.advance(9);
    stopwatch.stop();

    ticker.advance(16);

    stopwatch.start();

        deferred.length = length;
    }

    /**
     * Advances the buffer index by the specified number of bytes.
     *
     * @param n the number of bytes to advance
     */
    public void advance(final int n) {
        index += n;
        if (index - start > deferred.length) {
            deferred.length = index - start;
        }
    }

    /**

            final int _identifier_authoritys = 6;
            final int _identifier_authorityi = _dst.index;
            _dst.advance(1 * _identifier_authoritys);
            final int _sub_authorityi = _dst.index;
            _dst.advance(4 * _sub_authoritys);

            _dst = _dst.derive(_identifier_authorityi);
            for (int _i = 0; _i < _identifier_authoritys; _i++) {

    // 4 expires
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(6, 8, 0, 1, 2, 5, 7, 9);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(6, 8, 0, 1, 2, 5, 7, 9);

    // 6 expires
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(8, 0, 1, 2, 5, 7, 9);
    ticker.advance(1, MILLISECONDS);

    cache.put(0, 10);
    cache.put(2, 30);

    fakeTicker.advance(999, MILLISECONDS);
    assertEquals(Integer.valueOf(30), cache.getIfPresent(2));
    fakeTicker.advance(1, MILLISECONDS);
    assertEquals(Integer.valueOf(30), cache.getIfPresent(2));
    fakeTicker.advance(1000, MILLISECONDS);
    assertEquals(null, cache.getIfPresent(0));
  }

  public void testExpireAfterWrite() {

                _dst.enc_ndr_long(_name_buffers);
                _dst.enc_ndr_long(0);
                _dst.enc_ndr_long(_name_bufferl);
                final int _name_bufferi = _dst.index;
                _dst.advance(2 * _name_bufferl);

                _dst = _dst.derive(_name_bufferi);
                for (int _i = 0; _i < _name_bufferl; _i++) {
                    _dst.enc_ndr_short(this.name.buffer[_i]);
                }

   * either the {@code x} or {@code y} data must have a non-zero population variance (i.e. {@code
   * xStats().populationVariance() > 0.0 || yStats().populationVariance() > 0.0}). The result is
   * guaranteed to be horizontal if there is variance in the {@code x} data but not the {@code y}
   * data, and vertical if there is variance in the {@code y} data but not the {@code x} data.
   *

  @CanIgnoreReturnValue
  public FakeTicker advance(long time, TimeUnit timeUnit) {
    return advance(timeUnit.toNanos(time));
  }

  /** Advances the ticker value by {@code nanoseconds}. */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  @CanIgnoreReturnValue
  public FakeTicker advance(long nanoseconds) {
    nanos.addAndGet(nanoseconds);
    return this;
  }

  private @Nullable Reader current;

  MultiReader(Iterator<? extends CharSource> readers) throws IOException {
    this.it = readers;
    advance();
  }

  /** Closes the current reader and opens the next one, if any. */
  private void advance() throws IOException {
    close();
    if (it.hasNext()) {
      current = it.next().openStream();
    }
  }

  @Override