C program to print one month calendar

C program to print one month calendar

Output:

Enter a year to print calendar:
2015
Enter the month:
9
Calendar for year: 2015
September

Sun  Mon  Tue  Wed  Thu  Fri  Sat
            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  

Implementation:

#include<stdio.h> char *mon_name[]={" ","January","February","March","April", "May","June","July","August","September", "October","November","December" }; int days[]={0,31,28,31,30,31,30,31,31,30,31,30,31}; int main(void) { int day,month,year,code,x,y,z,cmonth; printf("Enter a year to print calendar: \n"); scanf("%d", &year); x=(year-1.)/4.0; y=(year-1.)/100.; z=(year-1.)/400.; code=(year+x-y+z)%7; if(year%4==0&&year%100!=0||year%400==0) days[2]=29; else days[2]=28; printf("Enter the month:\n"); scanf("%d",&cmonth); month=cmonth; printf("Calendar for Year: %d\n",year); for(month=1;month<=12;month++) { if(month==cmonth) { printf("%s",mon_name[month]); printf("\n\nSun Mon Tue Wed Thu Fri Sat\n" ); for(day=1; day<=1+code*5; day++) { printf(" "); } for(day=1;day<=days[month];day++) { printf("%2d",day); if((day+code)%7>0) printf(" "); else printf("\n "); } } code=(code+days[month])%7; } }