public void TestForNumberOfDifferentSolutions(int n, int expectedNumOfSolutions)
        {
            var result = ChallengeSolution.Solve(n);

            Assert.IsTrue(result.Count() == expectedNumOfSolutions);
        }
 public void CheckInvalidInputs()
 {
     Assert.Throws <ArgumentException>(() => ChallengeSolution.Solve(0));
     Assert.Throws <ArgumentException>(() => ChallengeSolution.Solve(-1));
 }