@Test
    public void testNFold () {
        // rfc3961 test vectors
        verifyNfold(64, "012345", "be072631276b1955");
        verifyNfold(56, "password", "78a07b6caf85fa");
        verifyNfold(64, "Rough Consensus, and Running Code", "bb6ed30870b7f0e0");
        verifyNfold(168, "password", "59e4a8ca7c0385c3c37b3f6d2000247cb6e6bd5b3e");

    Random r = new Random(9);
    for (int i = 0; i < ITERS; i++) {
      countRemaps(r.nextLong(), map);
    }
    for (int shard = 2; shard <= MAX_SHARDS; shard++) {
      // Rough: don't exceed 1.2x the expected number of remaps by more than 20
      assertTrue(map.get(shard) <= 1.2 * ITERS / shard + 20);
    }
  }

  private void countRemaps(long h, AtomicLongMap<Integer> map) {

     * forms are equivalent (though not necessarily minimal, though we hope this
     * to be the case). Thus, this test is more of a regression test.
     *
     * Rough instructions to regenerate the test outputs and verify correctness:
     * - Temporarily change this test:
     * --- Comment out assertEquals.
     * --- System.out.println(input + " " + simplifyPath(input));

     * forms are equivalent (though not necessarily minimal, though we hope this
     * to be the case). Thus, this test is more of a regression test.
     *
     * Rough instructions to regenerate the test outputs and verify correctness:
     * - Temporarily change this test:
     * --- Comment out assertEquals.
     * --- System.out.println(input + " " + simplifyPath(input));

   */
  @Override
  public String toString() {
    if (isEmpty()) {
      return "[]";
    }
    StringBuilder builder = new StringBuilder(length() * 5); // rough estimate is fine
    builder.append('[').append(array[start]);

    for (int i = start + 1; i < end; i++) {
      builder.append(", ").append(array[i]);
    }
    builder.append(']');

   */
  @Override
  public String toString() {
    if (isEmpty()) {
      return "[]";
    }
    StringBuilder builder = new StringBuilder(length() * 5); // rough estimate is fine
    builder.append('[').append(array[start]);

    for (int i = start + 1; i < end; i++) {
      builder.append(", ").append(array[i]);
    }
    builder.append(']');

   */
  @Override
  public String toString() {
    if (isEmpty()) {
      return "[]";
    }
    StringBuilder builder = new StringBuilder(length() * 5); // rough estimate is fine
    builder.append('[').append(array[start]);

    for (int i = start + 1; i < end; i++) {
      builder.append(", ").append(array[i]);
    }
    builder.append(']');

    Random r = new Random(9);
    for (int i = 0; i < ITERS; i++) {
      countRemaps(r.nextLong(), map);
    }
    for (int shard = 2; shard <= MAX_SHARDS; shard++) {
      // Rough: don't exceed 1.2x the expected number of remaps by more than 20
      assertTrue(map.get(shard) <= 1.2 * ITERS / shard + 20);
    }
  }

  private void countRemaps(long h, AtomicLongMap<Integer> map) {