CSC301: Put: One last question [19/30]

    public void put (int key) {
        root = put (root, key);
    }
    private static Node put (Node x, int key) {
        if (x == null)
            return new Node (key);
        if (key < x.key)
            x.left  = put (x.left,  key);
        else if (key > x.key)
            x.right = put (x.right, key);
        // what do I return here?
    }

Try inserting two things into an empty tree.

We need to remember the root.