public void NaiveThrowsForNegativeValues()
        {
            Action action1 = () => FibonacciNumbers.Naive(-1);

            action1.ShouldThrow <ArgumentException>();
            Action action2 = () => FibonacciNumbers.Naive(-10);

            action2.ShouldThrow <ArgumentException>();
        }
 public void NaiveWorks(long n, long fibn)
 {
     FibonacciNumbers.Naive(n).Should().Be(fibn);
 }
 public void NaiveBaseCases()
 {
     FibonacciNumbers.Naive(0).Should().Be(0);
     FibonacciNumbers.Naive(1).Should().Be(1);
 }