docs: public int getValueId(Clusterable c) {
  		currentItems++;
  		/*
  		 * if(isLeafNode()) { return id; }
  		 */
  		int index = TreeUtils.findNearestNodeIndex(subNodes, c);
  		if (index >= 0) {
  			KMeansTreeNode node = subNodes.get(index);
  			return node.getValueId(c);
  		}
  		return id;
  	}