}
      T result = output(index);
      toRemove = index;
      index++;
      return result;
    }

    @Override
    public void remove() {
      checkRemove(toRemove >= 0);
      if (counts[toRemove] > 0) {
        distinctElements--;
        size -= counts[toRemove];
        counts[toRemove] = 0;
      }
      toRemove = -1;
    }
  }

  @Override