public override Container or(BitsetContainer x)
 {
     return x.or((ArrayContainer) this);
 }
 public override Container or(BitsetContainer x)
 {
     return(x.or((ArrayContainer)this));
 }
 public override Container ior(BitsetContainer x)
 {
     return x.or(this);
 }
 public override Container ior(BitsetContainer x)
 {
     return(x.or(this));
 }