//Program to display calender for a given year
#include
#include
#include
#include
unsigned long days=0;
//stores the days elapsed since 01.01.1899
void display(int n)
//contains the number of days to display
{
int i, column, k, flag=0, j;
printf("Sun Mon Tues Wed Thur Fri Sat
");
for(i=1; i<=n; i++)
{
k=days%7;//remainder gives the starting day of each month
if(flag==0)
{
for(j=1; j<=k; j++)//controls tabs of first week
printf(" ");
flag=1;//ensures that block is only executed once
column=k;
}
printf("%d ", i);
column++;
if(column%7==0)//prints new line at the end of each week
printf("
");
}
printf("
Press any key to continue
");
getch();
}
void calculate(int year)
//function calculates no. of days elapsed since 1899
{
int i, month;
for(i=1899; i
{
if((i%400==0)?1:((i%100==0)?0:((i%4==0)?1:0)))
/*This is because a leap year does not strictly fall on every
fourth year. If a year is divisible by 4, then it is a leap
year, but if that year is divisible by 100, then it is
not a leap year. However, if the year is also divisible by
400, then it is a leap year. Eg: 1900 is not a leap year*/
days+=366;
else
days+=365;
}
for(month=1; month<=12; month++)
{
printf("
");
switch(month)
/*switch case used to display each month and
increment no. of days*/
{
case 1: printf(" JANUARAY %d
", year);
display(31);
days+=31;
break;
case 2: printf(" FEBURARY %d
", year);
if((year%400==0)?1:((year%100==0)?0:((year%4==0)?1:0)))
{
display(29);
days+=29;
}
else
{
display(28);
days+=28;
}
break;
case 3: printf(" MARCH %d
", year);
display(31);
days+=31;
break;
case 4: printf(" APRIL %d
", year);
display(30);
days+=30;
break;
case 5: printf(" MAY %d
", year);
display(31);
days+=31;
break;
case 6: printf(" JUNE %d
", year);
display(30);
days+=30;
break;
case 7: printf(" JULY %d
", year);
display(31);
days+=31;
break;
case 8: printf(" AUGUST %d
", year);
display(31);
days+=31;
break;
case 9: printf(" SEPTEMBER %d
", year);
display(30);
days+=30;
break;
case 10: printf(" OCTOBER %d
", year);
display(31);
days+=31;
break;
case 11: printf(" NOVEMBER %d
", year);
display(30);
days+=30;
break;
case 12: printf(" DECEMBER %d
", year);
display(31);
days+=31;
break;
}
}
}
void main()
{
char ch[10];
int i, year, choice;
do
{
clrscr();
days=0;
printf("Enter the year in 'yyyy' format:
");
scanf("%s", ch);//stores input first as a string
for(i=0; i
{
printf("
Invalid Year!");
printf("
END OF PROGRAM");
getch();
exit(0);
}
year = atoi(ch);
//converts the year from string to integer datatype
clrscr();
printf("
Calender for Year %d", year);
printf("
**********************
");
calculate(year);
//calls function to calculate no. of days elapsed
printf("
*******************************************
");
printf("
Press 1 to continue, 2 to exit
");
scanf("%d", &choice);
}while(choice==1);
clrscr();
printf("
END OF PROGRAM");
getch();
}