public static string TreePreorderBypass_NewCompareInt_Test(int[] array)
        {
            string s = "";

            Tree<int> tree = new Tree<int>(new CompareInt());

            foreach (int a in array)
                tree.AddNode(a);

            foreach (int a in tree.PreorderIterator())
                s += a;

            Debug.WriteLine(s);

            return s;
        }
        public void TreePreorderBypass_NewCompareString_Test()
        {
            string s = "";
            string[] array = new string[] { "500", "40", "5", "37", "1000", "10000" };

            Tree<string> tree = new Tree<string>(new CompareString());

            foreach (var a in array)
                tree.AddNode(a);

            foreach (var a in tree.PreorderIterator())
                s += a;

            Assert.AreEqual(s, "50040537100010000");
        }