}

    // This implementation is patterned after ConcurrentHashMap, but without the locking. The only
    // way for it to return a false negative would be for the target value to jump around in the map
    // such that none of the subsequent iterations observed it, despite the fact that at every point
    // in time it was present somewhere int the map. This becomes increasingly unlikely as

      list.set(0, 0);
    }
    // Get threshold in the range [0, length], rounding up to ensure that
    // non-zero percent values result in a non-zero threshold (so we always
    // have at least one matching character).
    int threshold = ((percent * length) + 99) / 100;
    StringBuilder builder = new StringBuilder(length);
    for (int n = 0; n < length; n++) {
      builder.append(