Thread: help with code - global variables

hi all,
the foll code prints a calender for year between 1900 & 2100. i have used 3 global vars - dayCount1, 2 & 3 to keep track of days. is there an alternative to using these global vars? any help will be appreciated. thanks in advance.

Code:

#include <stdio.h>

#define TRUE		1
#define FALSE		0
#define MIN_YEAR	1900
#define MAX_YEAR	2100
#define START_DAY	2
#define DAYS_IN_WEEK	7
#define MONTHS_IN_YEAR	12


int checkYear		(void);
int isLeap		(int);
int calcStartDayYear	(int);
int printCalender	(int, int, int[], int, int);


int dayCount1 = 0;
int dayCount2 = 0;
int dayCount3 = 0;



int main()
{
	int days[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31};
	int year = 0;
	int leapResult = 0;
	int startDay = 0;
	int monthsInRow = 0;
	int daysInRow  = 0;


	printf("\nEnter a year between 1900 and 2100 : ");
	year = checkYear();

	leapResult = isLeap(year);
	startDay = calcStartDayYear(year);

	printf("\n\n\t\t\t\t\t%d\n\n", year);
	for(monthsInRow = 0; monthsInRow <12; monthsInRow += 3)
	{
		switch(monthsInRow)
		{
			case 0:
				dayCount1 = 0;
				dayCount2 = 0;
				dayCount3 = 0;

				printf("\tJan\t \t\t\tFeb\t \t\t\tMar\n");
				break;
			case 3:
				dayCount1 = 0;
				dayCount2 = 0;
				dayCount3 = 0;

				printf("\tApr\t \t\t\tMay\t \t\t\tJun\n");
				break;
			case 6:
				dayCount1 = 0;
				dayCount2 = 0;
				dayCount3 = 0;

				printf("\tJul\t \t\t\tAug\t \t\t\tSep\n");
				break;	
			case 9:
				dayCount1 = 0;
				dayCount2 = 0;
				dayCount3 = 0;

				printf("\tOct\t \t\t\tNov\t \t\t\tDec\n");
				break;
		}
		printf("  S  M Tu  W Th  F  S\t\t");
		printf("  S  M Tu  W Th  F  S\t\t");
		printf("  S  M Tu  W Th  F  S\n");
		
		for(daysInRow = 0; daysInRow < 6; daysInRow++)
		{
			startDay = printCalender(monthsInRow + 1, year, days, startDay, daysInRow);
			startDay = printCalender(monthsInRow + 2, year, days, startDay, daysInRow);
			startDay = printCalender(monthsInRow + 3, year, days, startDay, daysInRow);
			printf("\n");
		}
		printf("\n");
	}
	printf("\n\n");
	return 0;
}

int checkYear()
{
	int year = 0;
	

	scanf("%d", &year);
	while( (year < MIN_YEAR) || (year > MAX_YEAR) )
	{
		printf("\nPlease enter year between 1900 and 2100 : ");
		scanf("%d", &year);
	}
	return year;
}

int isLeap(int year)
{
	if( (year % 400 == 0) || ((year % 4 == 0) && (year % 100 != 0)) )
	{
		return TRUE;
	}
	return FALSE;
}

int calcStartDayYear(int year)
{
	int yearCount = 0;
	int startDayNextYear = START_DAY;
	

	for(yearCount = MIN_YEAR; yearCount < year; yearCount++)
	{
		if( isLeap(yearCount) )
		{
			startDayNextYear += 2;
		}
		else
		{
			startDayNextYear += 1;
		}
		if(startDayNextYear == 8)
		{
			startDayNextYear = 1;
		}
		else if(startDayNextYear == 9)
		{
			startDayNextYear = 2;
		}
	}
	return startDayNextYear;
}

int printCalender(int month, int year, int days[], int startDay, int daysInRow)
{
	int daysInMonth[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
	int dayOfWeek[] = {1, 2, 3, 4, 5, 6, 7};
	int colCount = 0;
	int index = 0;	


	if(daysInRow == 0)
	{
		while(dayOfWeek[index] != startDay)
		{
			printf("   ");
			index++;
			colCount++;
		}
		if( (month == 2) && (isLeap(year)) )
		{
			daysInMonth[month] = 29;
		}
		startDay = (startDay + daysInMonth[month]) % DAYS_IN_WEEK;
		if(startDay == 0)
		{
			startDay = 7;
		}
	}
	while(colCount <= 6)
	{	
		if( (month == 1) || (month == 4) || (month == 7) || (month == 10) )
		{
			if(dayCount1 < daysInMonth[month])
			{
				printf(" %2d", days[dayCount1]);
				dayCount1++;
				colCount++;
			}
			else
			{
				while(colCount <= 6)
				{
					printf("   ");
					colCount++;
				}
			}
		}
		else if( (month == 2) || (month == 5) || (month == 8) || (month == 11) )
		{
			if( (month == 2) && (isLeap(year)) )
			{
				daysInMonth[month] = 29;			
			}
			if(dayCount2 < daysInMonth[month])
			{
				printf(" %2d", days[dayCount2]);
				dayCount2++;
				colCount++;
			}
			else
			{
				while(colCount <= 6)
				{
					printf("   ");
					colCount++;
				}
			}
		}
		else
		{
			if(dayCount3 < daysInMonth[month])
			{
				printf(" %2d", days[dayCount3]);
				dayCount3++;
				colCount++;
			}
			else
			{
				while(colCount <= 6)
				{
					printf("   ");
					colCount++;
				}
			}
		}
	}
	printf("\t\t");

	return startDay;
}

i used static variables in printCalender() but couldn't re-initialize them for the next 3 months & so on... abt calling printCalender() just once for 3 months, sld i change the code so that i print 6 rows inside the function? thanks.

thank you so much. i implemented the second maethod u told me. it works just great!!!