Enter month number (1-12), or 0 to quit: 3
Enter day of month: 1
Enter year: 2005
1 Mar 2005 is day number 60

Enter month number (1-12), or 0 to quit: 3
Enter day of month: 1
Enter year: 2004
1 Mar 2004 is day number 61

Enter month number (1-12), or 0 to quit: 15
Enter day of month: 3
Enter year: 1500
Sorry, but year must be 1600 or later.
The month must be in the range 1 to 12.

Enter month number (1-12), or 0 to quit: 6
Enter day of month: 31
Enter year: 2005
The day must be in the range 1-30 for Jun.

Enter month number (1-12), or 0 to quit: 2
Enter day of month: 29
Enter year: 2005
The day must be in the range 1-28 for Feb.

Enter month number (1-12), or 0 to quit: 2
Enter day of month: 29
Enter year: 2000
29 Feb 2000 is day number 60

Enter month number (1-12), or 0 to quit: 0