public static void testSerializeTree()
    {
        TreeNode root = new TreeNode("0");
        TreeNode node1 = new TreeNode("1");
        TreeNode node2 = new TreeNode("2");
        TreeNode node3 = new TreeNode("3");
        TreeNode node4 = new TreeNode("4");

        root.setLeft(node1);
        root.setRight(node2);
        node1.setLeft(node3);
        node1.setRight(node4);

        if(BasicQuestions.serializeTree(root))
            System.out.println("Success !");
        else
            System.out.println("Booooo !");
    }