code: private static int getSizeNoH(Group g) {
  		int size = 0;
  		for (Atom a:g.getAtoms()) {
  			if (a.getElement()!=Element.H)
  				size++;
  		}
  		return size;
  	}
docs: Calculates the number of non-Hydrogen atoms in the given group
  @param g
  @return