How to Use the C language to implement the 10 thousand calendar and the C language to implement Perpetual Calendar

How to Use the C language to implement the 10 thousand calendar and the C language to implement Perpetual Calendar
The program simply enters a year (year after 1901), and then the program outputs the calendar of the Year 12 months.

# Include # define Mon 1 # define Tues 2 # define Wed 3 # define Thur 4 # define Fri 5 # define Sat 6 # define Sun 0 # define January_days 31 # define February_days 28 # define march_days 31 # define versions 30 # define May_days 31 # define June_days 30 # define versions 31 # define versions 31 # define versions 30 # define October_days 31 # define emnovber_days 30 # define December_days 31 first1month January_days # d Efine first2month duration + duration # define first3month duration + March_days # define first4month duration + March_days + duration # define first5month duration + May_days # define first6month duration + february_days + March_days + April_days + May_days + June_days # define first7month January_days + February_days + March_days + April_day S + May_days + June_days \ + region # define first8month region + March_days + region + May_days + June_days \ + region # define first9month region + February_days + March_days + region + May_days june_days \ + week + August_days + week # define first10month January_days + February_days + March_days + April_days + May_days + June_days \ + week + August_days + week + Oct Ober_days # define first11month week + February_days + March_days + week + May_days + June_days \ + week + October_days + week = 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 first3mon Th; 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: retu Rn "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 a month of a year by format */void first_line_print (int month, int year) {// printf ("% 20 s % d \ n ", month_name (month), year); printf ("% 8d year % s \ n", year, month_name (Month);}/* print the name of the week by format */void week_print () {// printf ("%-6 s %-6 s %-6 s %-6 s %-6 s %-6 s %-6 s %-6s \ n", "Sun. "," Mon. "," Tues. "," Wed. "," Thur. "," Fri. "," Sat. "); printf (" %-3 s %-3 s %-3 s %-3 s %-3 s %-3 s %-3 s \ n ", "," 1 "," 2 "," 3 "," 4 "," 5 "," 6 ");} /* calculate the number of days 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 {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 ++ ;}} elseif (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 day of the week on the first day of the month */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; retur N weekday;}/* print the day of the month in sequence */void print_in_turn (int month, int firstday, int year) {int I = 1; int weekday; switch (firstday) {case Sun: break; case Mon: printf ("%-3 s", ""); break; case Tues: printf ("%-6 s ",""); break; case Wed: printf ("%-9 s", ""); break; case Thur: printf ("%-12 s", ""); break; case Fri: printf ("%-15 s", ""); break; case Sat: printf ("%-18 s", ""); break ;} switch (month) {case 1: case 3: case 5: case 7: case 8: case 10: case 12: {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/* year */{for (I = 0; I <28; I ++) {weekday = (firstday + I) % 7; printf ("%-3d", I + 1); if (weekday = Sat) {printf ("\ n") ;}} break ;}case 4: case 6: case 9: case 11: {for (I = 0; I <30; I ++) {weekday = (firstday + I) % 7;/* calculate the day of the week */printf ("%-3d", I + 1 ); if (weekday = Sat) {printf ("\ n");/* if it is Saturday, line feed */} break ;}} 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");} void main_calendar (int year) {int I; for (I = 1; I <= 12; I ++) {main_month (I, year) ;}} int main () {int year; printf ("Enter the year: year ="); scanf ("% d", & year); printf ("\ n"); while (year <1902) {printf ("Enter year \ n greater than 1901"); printf ("Enter year: year ="); scanf ("% d", & year ); printf ("\ n");} main_calendar (year); scanf (""); return 0 ;}

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