public static LinkedList<Tuple<String, LinkedList<Triple<String,String,String>>>> relation_sort(Hashtable<String, LinkedList<Triple<String,String,String>>> relations){
		Set<String> key_set = relations.keySet();
		LinkedList<Tuple<String, LinkedList<Triple<String,String,String>>>> result = new LinkedList<Tuple<String, LinkedList<Triple<String,String,String>>>>();
		Iterator<String> iter = key_set.iterator();
		String current = "";
		while(iter.hasNext()){
			current = iter.next();
			result = insert(result, new Tuple<String, LinkedList<Triple<String,String,String>>>(current, relations.get(current)));
		}
		return result;
	}