C language implementation of a million calendar applet _c language

The program simply enters a year (years after 1901), and then the program prints the calendar for the year 12 months.

#include <stdio.h> #define MON 1 #define Tues 2 #define WED 3 #define THUR 4 #define FRI 5 #define SAT 6 #define SUN 0 #define JANUARY_DAYS #define FEBRUARY_DAYS #define MARCH_DAYS #define April_days #d  Efine may_days #define JUNE_DAYS #define JULY_DAYS #define AUGUST_DAYS #define #define OCTOBER_DAYS #define NOVEMBER_DAYS #define DECEMBER_DAYS #define First1month january_days #defi NE first2month january_days+february_days #define FIRST3MONTH january_days+february_days+march_days #define First4month january_days+february_days+march_days+april_days #define First5month January_days+february_days+march_ Days+april_days+may_days #define First6month January_days+february_days+march_days+april_days+may_days+june_days # Define First7month january_days+february_days+march_days+april_days+may_days+june_days \ +July_days #define Firs T8month January_days+february_days+march_days+april_daYs+may_days+june_days \ +july_days+august_days #define First9month january_days+february_days+march_days+april_d Ays+may_days+june_days \ +july_days+august_days+september_days #define First10month january_days+february_days+m Arch_days+april_days+may_days+june_days \ +july_days+august_days+september_days+october_days #define First11mont H january_days+february_days+march_days+april_days+may_days+june_days \ +july_days+august_days+september_days+oc
tober_days+november_days int known_weekday = Tues;
int known_year = 1901;
int konwn_month = 1;

int known_day = 1;
		int day_count (int month) {switch (month) {case 1:return 0;break;
		Case 2:return First1month;break;
		Case 3:return First2month;break;
		Case 4:return First3month;break;
		Case 5:return First4month;break;
		Case 6:return First5month;break;
		Case 7:return First6month;break;
		Case 8:return First7month;break;
		Case 9:return First8month;break; Case 10:return First9month;break;
		Case 11:return First10month;break;
	Case 12:return First11month;break;
			}/*char * Month_name (int month) {switch (month) {case 1:return ' January ';
		Break
			Case 2:return "February";
		Break
			Case 3:return "March";
		Break
			Case 4:return "April";
		Break
			Case 5:return "may";
		Break
			Case 6:return "June";
		Break
			Case 7:return "July";
		Break
			Case 8:return "August";
		Break
			Case 9:return "September";
		Break
			Case 10:return "October";
		Break
			Case 11:return "November";
		Break
			Case 12:return "December";
		Break
	Default:break;
			}}*/char * month_name (int month) {switch (month) {case 1:return "January";
		Break
			Case 2:return "February";
		Break
			Case 3:return "March";
		Break
			Case 4:return "April";
		Break
			Case 5:return "May";
		Break
			Case 6:return "June";
		Break
			Case 7:return "July";
		Break
			Case 8:return "August";
		Break Case 9:rEturn "September";
		Break
			Case 10:return "October";
		Break
			Case 11:return "November";
		Break
			Case 12:return "December";
		Break
	Default:break;
	}//* Print the name of the month in the format/void first_line_print (int month, int year) {//printf ("%20s%d \ n", Month_name (month), year);
printf ("%8d%s \ n", year, Month_name (month));  */* Print week name in format/void Week_print () {//printf ("%-6s%-6s%-6s%-6s%-6s%-6s%-6s\n", "Sun.", "Mon.", "Tues.", "Wed.", "Thur.",
	"Fri.", "Sat.");
printf ("%-3s%-3s%-3s%-3s%-3s%-3s%-3s\n", "Day", "one", "two", "three", "four", "five", "six");
	}/* Calculates the distance between the month and the known day of the year/int date_distance_count (int month, int year) {int leap_year_count = 0;
	int i;

	int distance; if (Year > Known_year) {for (i=known_year i<year; i++) {if ((i%4 = 0) && (i%100!= 0)) | |
			(i%400 = 0))		
			{leap_year_count++; } if (Month > 2) {if ((year%4 = = 0) && (year%100!= 0) | |
			(year%400 = 0))		
			{leap_year_count++;
}} else if (year = = Known_year) {		if (Month > 2) {leap_year_count = 1;

	} distance = (year-known_year) *365 + Leap_year_count + day_count (month);	
return distance;
	/* Determine the first day of the month is the Week/int makesure_firstday_weekday (int month, int year) {int date_distance = 0;

	int weekday;
	Date_distance = Date_distance_count (month, year);

	Weekday = (Known_weekday + date_distance)%7;	
return weekday;
	}//* Print out the day of the Month/void Print_in_turn (int month, int firstday, int year) {int i = 1;

	int weekday;
		Switch (firstday) {case sun:break;
			Case mon:printf ("%-3s", "");
		Break
			Case tues:printf ("%-6s", "");
		Break
			Case wed:printf ("%-9s", "");
		Break
			Case thur:printf ("%-12s", "");
		Break
			Case fri:printf ("%-15s", "");
		Break
			Case sat:printf ("%-18s", "");
	Break 
			Switch (month) {case 1:case 3:case 5:case 7:case 8:case 10:case-for (i=0; i<31; i++)
				{weekday = (FirstDay + i)%7;
				
				printf ("%-3d", i+1); if (weekday == Sat) {printf ("\ n");
		}} break; Case 2: {if ((year%4 = 0) && (year%100!= 0) | | (year%400 = 0))
					/* Leap Year * * for (i=0 i<29; i++) {weekday = (FirstDay + i)%7;
					
					printf ("%-3d", i+1);
					if (weekday = Sat) {printf ("\ n");
			}} break;
					else/* excepting/{for (i=0 i<28; i++) {weekday = (FirstDay + i)%7;
					
					printf ("%-3d", i+1);
					if (weekday = Sat) {printf ("\ n");
			}} break; 4:case 6:case 9:case: {for (i=0; i<30; i++) {weekday = (FirstDay + i)%7;/* calculate the day
				
				Is the day of the week */printf ("%-3d", i+1);
		if (weekday = Sat) {printf ("\ n");/* If it is Saturday, then break the line */}};

	}} void Date_print (int month, int year) {int firstday;
	FirstDay = Makesure_firstday_weekday (month, year);
	Print_in_turn (month, FirstDay, year);
printf ("\ n");
} void Main_month (int month, int year){first_line_print (month, year);
	Week_print ();
	Date_print (month, year);
printf ("\ n \ nthe");
	} void Main_calendar (int year) {int i;
	For (i=1. i<=12; i++) {main_month (I, year);

	int main () {int year;
	printf ("Please enter year: years =");
	scanf ("%d", &year);

	printf ("\ n");

		while (year < 1902) {printf ("Please enter an age greater than 1901 \ n");
		printf ("Please enter year: years =");
		scanf ("%d", &year);
	printf ("\ n");
	
	} Main_calendar (year);
	scanf ("");
return 0; }

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