public void Two_Digits_Return_3Times()
 {
     Assert.AreEqual(3, PersistentBugger.Persistence(39));
 }
 public void Four_Digits_Return_1Times()
 {
     Assert.AreEqual(1, PersistentBugger.Persistence(1111));
 }
 public void Two_Digits_Return_2Times()
 {
     Assert.AreEqual(2, PersistentBugger.Persistence(25));
 }
 public void Three_Digits_Return_4Times()
 {
     Assert.AreEqual(4, PersistentBugger.Persistence(999));
 }
 public void One_Digits_Return_0Times()
 {
     Assert.AreEqual(0, PersistentBugger.Persistence(4));
 }