private Value get(STNode<Key, Value> x, Key key)
	{
		if (x == null)
			return null; // Leaves reached. Key not found.

		int cmp = key.compareTo(x.key);
		if (cmp < 0)
			return get(x.left, key); // search left subtree recursively
		else if (cmp > 0)
			return get(x.right, key); // search right subtree recursively
		else
			return x.val;// cmp == 0. Key found
	}