public Enumerator(LevelBag <E, K> parent)
{
this.parent = parent;
l = parent.level.Length - 1;
size = (int)parent.size;
}
public Level(uint level, uint numElements, LevelBag <E, K> levelBag) : base()
{
items = new HashSet <E>();
this.thisLevel = level;
this.parent = levelBag;
}