Phone Book is empty
Sally's number has been added to the phonebook
Fred's number has been added to the phonebook
Phone Book by name
 Fred 5552222
 Sally 5551111
Phone Book by number
 5551111 Sally
 5552222 Fred
Sally's number is 5551111
Fred's number is 5552222
No entry for Rachel
Sally is calling!
Fred is calling!
Unknown Caller!
Sally's number has changed from 5551111 to 5554444
Sally's number is 5554444
Unknown Caller!
Phone Book by name
 Fred 5552222
 Sally 5554444
Phone Book by number
 5552222 Fred
 5554444 Sally
Fred must have moved, the number 5552222 now belongs to Rachel
Rachel's number has been added to the phonebook
Phone Book by name
 Rachel 5552222
 Sally 5554444
Phone Book by number
 5552222 Rachel
 5554444 Sally
Rachel is calling!
Rachel's number is 5552222
No entry for Fred