#  Friday13.py  Copyright (c) Kari Laitinen

#  http://www.naturalprogramming.com

#  2006-05-01  File created.
#  2009-01-22  class ISODate used in place of Date
#  2022-12-18  Converted to Python 3.

#  In the pythonfilesextra folder you can find a program
#  named Friday13Faster.py which is a faster version of
#  this program.

from ISODate import ISODate

print( "\n This program can print you a list of 10 dates"    \
      "\n that are Fridays and 13th days of a month."       \
      "\n Please, type in a date from which you want"       \
      "\n the calculation to begin. Type in the date"       \
      "\n in form YYYY-MM-DD and use two digits for days"   \
      "\n and months and four digitsfor the year:  ", end="" )

given_date_as_string  =  input()

date_to_increment  =  ISODate( given_date_as_string )

number_of_friday13_dates_to_print  =  10

print( "\n It is a common belief that you may have"  \
       "\n bad luck on the following dates:" )

while  number_of_friday13_dates_to_print  >  0  :

   while  date_to_increment.index_for_day_of_week()  !=  4  or  \
          date_to_increment.day()  !=  13   :

      date_to_increment.increment()

   print( "\n    %s, %s"  %  ( date_to_increment,
          date_to_increment.get_day_of_week() ), end="" )

   date_to_increment.increment()
   number_of_friday13_dates_to_print  -=  1

print( "\n" )