public void Correct_number_of_results(int size, int expected)
{
var set = new[] { 1, 2, 3, 4, 5 };
var permutations = new PermutationService().GetPermutations(set, size);
Assert.That(permutations.Count(), Is.EqualTo(expected));
}
public void No_permutations_have_the_same_exact_items()
{
var set = new[] { 1, 2, 3, 4, 5 };
var permutations = new PermutationService().GetPermutations(set, 3);
var permutationsWithSameItems = permutations
.Select(permutation => permutation.OrderBy(x => x))
.Distinct();
Assert.That(permutations.Count(), Is.EqualTo(permutationsWithSameItems.Count()));
}