public void CalculatePersistence_OnKnowns_ShouldReturnProperResults(ulong input, int expected)
{
var persistence = new Persistence();
persistence.CalculatePersistence(input).Should().Be(expected);
}
public void PersistNumberphileNumber_ShouldHavePersistenceOf11()
{
var persistence = new Persistence();
persistence.CalculatePersistence(277777788888899).Should().Be(11);
}