public void Add10000()
        {
            var coll = new AvlBinaryTreeCollection <int>();

            for (int i = 0; i < 10000; i++)
            {
                coll.Add(i);
            }
            for (int i = 0; i < 10000; i++)
            {
                Assert.That(coll.Contains(i), Is.True);
            }
            Assert.That(coll.Count, Is.EqualTo(10000));
            Assert.That(coll.First, Is.EqualTo(0));
            Assert.That(coll.Last, Is.EqualTo(10000 - 1));
            Assert.That(coll, Is.EquivalentTo(Enumerable.Range(0, 10000)));
        }
        public void ContainsForEmpty()
        {
            var coll = new AvlBinaryTreeCollection <int>();

            Assert.That(coll.Contains(0), Is.False);
        }