@Override
	public DVector getCommonPreRequisites(Ability A)
	{
		DVector preReqs=getRawPreRequisites("All", false, A.ID());
		if(preReqs==null)
		{
			for(final Map<String,AbilityMapping> ableMap : completeAbleMap.values())
			{
				if(ableMap.containsKey(A.ID()))
				{
					preReqs=ableMap.get(A.ID()).skillPreReqs();
					if((preReqs!=null)&&(preReqs.size()>0))
						break;
				}
			}
		}
		if((preReqs==null)||(preReqs.size()==0))
			return new DVector(2);
		final DVector requisites=preReqs.copyOf();
		fillPreRequisites(A,requisites);
		return requisites;
	}