#ifndef _CALENDAR_H
#define _CALENDAR_H

/********

Do NOT modify this file.
Write functions in a separate file
and include "calendar.h"

********/

/***** 
Notes:

1. We use this convention for weekdays:
    1 = Sunday
    2 = Monday
    3 = Tuesday
    4 = Wednesday
    5 = Thursday
    6 = Friday
    7 = Saturday

2. We use the convention for months:
    1 = January
    2 = February
    ...
    12 = December

*****/


/* January 1, 1900 was a Monday */

#define FirstYear 1900
#define FirstYearWeekday 2


/* Function Prototypes */

/* GetYear() 
     Prompt the user for the calendar year.
     Make sure that the year is not before FirstYear,
        otherwise keep bugging the user.
*/
int GetYear() ;


/* WeekdayJan1(int year) 
     Return the day of the week for January 1 for the given year.
*/
int WeekdayJan1(int year) ;


/* PrintLabel(int month, int year) 
     Prints a nice label like "August 2012" centered over the
     monthly calendar.
*/

void PrintLabel(int month, int year) ;


/* int NumberDays(int month, int year) 
      Return the number of days in the given month.
      The year parameter is needed for leap years.
*/

int NumberDays(int month, int year) ;


/* PrintMonth(int days, int weekday)
      Print a monthly calendar for a month that
      has 'days' days and begins on the given weekday.
*/

void PrintMonth(int days, int weekday) ;


/* int SarahsFunction(int days, int weekday) 
      Return the weekday of the day that is 
      'days' days after the given weekday.
      For example, if August starts on a
      Wednesday, then SarahsFunction(31, 4)
      will tell you that September starts
      on Saturday.
*/

int SarahsFunction(int days, int weekday) ;


/* int isLeapYear(int year)
      Return 1 if the given year is a leap year.
      Otherwise returns 0.
*/

int isLeapYear(int year) ;

#endif