# include <stdio.h>
# include <stdbool.h>
//
//  Program 9.3, Stephen Kochan, Programming in C.
//
struct date
{
  int month;
  int day;
  int year;
};

int main ( void );
int numberOfDays ( struct date d );
bool isLeapYear ( struct date d );

int main ( void )
{
  struct date today, tomorrow;

  printf ( "Enter today's date (mm dd yyyy): \n" );
  scanf ( "%i%i%i", &today.month, &today.day, &today.year );

  if ( today.day != numberOfDays ( today ) )
  {
    tomorrow.day = today.day + 1;
    tomorrow.month = today.month;
    tomorrow.year = today.year;
  }
  else if ( today.month == 12 )
  {
    tomorrow.day = 1;
    tomorrow.month = 1;
    tomorrow.year = today.year + 1;
  }
  else
  {
    tomorrow.day = 1;
    tomorrow.month = today.month + 1;
    tomorrow.year = today.year;
  }  

  printf ( "Tomorrow's date is is %i/%i/%.2i.\n", tomorrow.month, tomorrow.day,
    tomorrow.year % 100 );

  return 0;
}
int numberOfDays ( struct date d )
{
  int days;
  bool isLeapYear ( struct date d );
  const int daysPerMonth[12] = { 31, 28, 31, 30, 31, 30,
                                 31, 31, 30, 31, 30, 31 };

  if ( isLeapYear ( d ) == true && d.month == 2 )
  {
    days = 29;
  }
  else
  {
    days = daysPerMonth[d.month-1];
  }
  return days;
}
bool isLeapYear ( struct date d )
{
  bool leapYearFlag;

  if ( ( d.year % 4 == 0 && d.year % 100 != 0 ) ||
       ( d.year % 400 == 0 ) )
  {
    leapYearFlag = true;
  }
  else
  {
    leapYearFlag = false;
  }
  return leapYearFlag;
}