public void Test4()
        {
            var ss     = new SmallestSubarray();
            int?result = ss.Smallest(new int[] { 1, 2, 4 }, 8);

            Assert.That(result, Is.Null);
        }
        public void Test2()
        {
            var ss     = new SmallestSubarray();
            int?result = ss.Smallest(new int[] { 1, 10, 5, 2, 7 }, 9);

            Assert.That(result, Is.EqualTo(1));
        }
        public void Test3()
        {
            var ss     = new SmallestSubarray();
            int?result = ss.Smallest(new int[] { 1, 11, 100, 1, 0, 200, 3, 2, 1, 250 }, 280);

            Assert.That(result, Is.EqualTo(4));
        }
        public void Test1()
        {
            var ss     = new SmallestSubarray();
            int?result = ss.Smallest(new int[] { 1, 4, 45, 6, 0, 19 }, 51);

            Assert.That(result, Is.EqualTo(3));
        }