public override void Save(BinaryWriter bw)
{
this.Commit ();
//global_num_lists++;
//int num_blocks = this.Count1 / this.B;
//double avg_filled = filled * 100.0 / num_blocks;
//global_avg_filled += avg_filled;
//Console.WriteLine ("ooooo> filled: {0}, num-blocks: {1}, ratio: {2}, avg-ratio: {3} ",
// filled, num_blocks, filled * 100.0 / num_blocks, global_avg_filled/global_num_lists);
base.Save (bw);
}