Notes

#include <stdio.h>
int isLeapYear(int year)
{
if ((year % 4) == 0)
{
if (year % 100 == 0)
{
if (year % 400 == 0)
{
return 1;
}
else
{
return 0;
}
}
return 1;
printf("nyes");
}
else
{
return 0;
printf("nno");
}
}

int toJulianNonLeap(int month, int day)
{
int coolMathNumber = 0;
{
switch (month)
{
case 12:
{
coolMathNumber = 334 + day;
return coolMathNumber;
break;
}
case 11:
{
coolMathNumber = 304 + day;
return coolMathNumber;
break;
}
case 10:
{
coolMathNumber = 273 + day;
return coolMathNumber;
break;
}
case 9:
{
coolMathNumber = 243 + day;
return coolMathNumber;
break;
}
case 8:
{
coolMathNumber = 212 + day;
return coolMathNumber;
break;
}
case 7:
{
coolMathNumber = 181 + day;
return coolMathNumber;
break;
}
case 6:
{
coolMathNumber = 151 + day;
return coolMathNumber;
break;
}
case 5:
{
coolMathNumber = 120 + day;
return coolMathNumber;
break;
}
case 4:
{
coolMathNumber = 90 + day;
return coolMathNumber;
break;
}
case 3:
{
coolMathNumber = 59 + day;
return coolMathNumber;
break;
}
case 2:
{
if (day > 28)
{
break;
}
else
coolMathNumber = 31 + day;
return coolMathNumber;
break;
}
case 1:
{
coolMathNumber = 0 + day;
return coolMathNumber;
break;
}
case 0:
{
return 0;
break;
}
}
}
}

int toJulianLeap(int month, int day)
{
int coolMathNumber = 0;

switch (month)
{
case 12:
{
coolMathNumber = 335 + day;
return coolMathNumber;
break;
}
case 11:
{
coolMathNumber = 305 + day;
return coolMathNumber;
break;
}
case 10:
{
coolMathNumber = 274 + day;
return coolMathNumber;
break;
}
case 9:
{
coolMathNumber = 244 + day;
return coolMathNumber;
break;
}
case 8:
{
coolMathNumber = 213 + day;
return coolMathNumber;
break;
}
case 7:
{
coolMathNumber = 182 + day;
return coolMathNumber;
break;
}
case 6:
{
coolMathNumber = 152 + day;
return coolMathNumber;
break;
}
case 5:
{
coolMathNumber = 121 + day;
return coolMathNumber;
break;
}
case 4:
{
coolMathNumber = 91 + day;
return coolMathNumber;
break;
}
case 3:
{
coolMathNumber = 60 + day;
return coolMathNumber;
break;
}
case 2:
{

coolMathNumber = 31 + day;
return coolMathNumber;
break;
}
case 1:
{
coolMathNumber = 0 + day;
return coolMathNumber;
break;
}
case 0:
{
return 0;
break;
}
}

}

int toJulian(int month, int day, int year)
{
int coolMathNumber = 0;
int anotherCoolMathNumber = 0;
anotherCoolMathNumber = isLeapYear(year);
if (anotherCoolMathNumber == 1)
{
coolMathNumber = toJulianLeap(month, day);
}
else
{
coolMathNumber = toJulianNonLeap(month, day);
}
printf("The date in Julian form is : %d / %d.nn", coolMathNumber, year);
return 0;
}

int toCalendarLeap(int julianday, int *newMonth, int *newDay)
{
if (julianday > 335)
{
*newDay = (julianday - 335);
*newMonth = 12;
return 0;
}
if (julianday > 305)
{
*newDay = (julianday - 305);
*newMonth = 11;
return 0;
}
if (julianday > 274)
{
*newDay = (julianday - 274);
*newMonth = 10;
return 0;
}
if (julianday > 244)
{
*newDay = (julianday - 244);
*newMonth = 9;
return 0;
}
if (julianday > 213)
{
*newDay = (julianday - 213);
*newMonth = 8;
return 0;
}
if (julianday > 182)
{
*newDay = (julianday - 182);
*newMonth = 7;
return 0;
}
if (julianday > 152)
{
*newDay = (julianday - 152);
*newMonth = 6;
return 0;
}
if (julianday > 121)
{
*newDay = (julianday - 121);
*newMonth = 5;
return 0;
}
if (julianday > 91)
{
*newDay = (julianday -91);
*newMonth = 4;
return 0;
}
if (julianday > 60)
{
*newDay = (julianday - 60);
*newMonth = 3;
return 0;
}
if (julianday > 31)
{
*newDay = (julianday - 31);
*newMonth = 2;
return 0;
}
if (julianday < 31)
{
*newDay = (julianday);
*newMonth = 1;
return 0;
}
return 0;
}

int toCalendarNonLeap(int julianday, int *newMonth, int *newDay)
{
if (julianday > 334)
{
*newDay = (julianday - 334);
*newMonth = 12;
return 0;
}
if (julianday > 304)
{
*newDay = (julianday - 304);
*newMonth = 11;
return 0;
}
if (julianday > 273)
{
*newDay = (julianday - 273);
*newMonth = 10;
return 0;
}
if (julianday > 243)
{
*newDay = (julianday - 243);
*newMonth = 9;
return 0;
}
if (julianday > 212)
{
*newDay = (julianday - 212);
*newMonth = 8;
return 0;
}
if (julianday > 181)
{
*newDay = (julianday - 181);
*newMonth = 7;
return 0;
}
if (julianday > 151)
{
*newDay = (julianday - 151);
*newMonth = 6;
return 0;
}
if (julianday > 120)
{
*newDay = (julianday - 120);
*newMonth = 5;
return 0;
}
if (julianday > 90)
{
*newDay = (julianday - 90);
*newMonth = 4;
return 0;
}
if (julianday > 59)
{
*newDay = (julianday - 59);
*newMonth = 3;
return 0;
}
if (julianday > 31)
{
*newDay = (julianday - 31);
*newMonth = 2;
return 0;
}
if (julianday < 31)
{
*newDay = (julianday);
*newMonth = 1;
return 0;
}
return 0;
}

int toCalendar(int julianday, int year)
{

int newDay = 0;
int newMonth = 0;
int coolMathNumber = 0;
int anotherCoolMathNumber = 0;

anotherCoolMathNumber = 0;
anotherCoolMathNumber = isLeapYear(year);
if (anotherCoolMathNumber == 1)
{
toCalendarLeap(julianday, &newMonth, &newDay);
}
else
{
toCalendarNonLeap(julianday, &newMonth, &newDay);
}


printf("The date in calendar form is : %d / %d / %d.nn", newMonth, newDay, year);
return 0;
}

int daysBetweenDates(int month1, int day1, int year1, int month2, int day2, int year2)
{
int year3 = 0;
int month3 = 0;
int day3 = 0;
int leapYear1 = 0;
int leapYear2 = 0;
int sumOfDays1 = 0;
int sumOfDays2 = 0;
int THEOUTPUT = 0;

if (isLeapYear(year1) == 1)
{
sumOfDays1 = sumOfDays1 + toJulianLeap(month1, day1);
}
else
{
sumOfDays1 = sumOfDays1 + toJulianNonLeap(month1, day1);
}

if (isLeapYear(year2) == 1)
{
sumOfDays2 = sumOfDays2 + toJulianLeap(month2, day2);
}
else
{
sumOfDays2 = sumOfDays2 + toJulianNonLeap(month2, day2);
}

for (; year1 != 0; year1--)
{
leapYear1 = 0;
leapYear1 = isLeapYear(year1);
if (leapYear1 == 1)
{
sumOfDays1 = sumOfDays1 + 366;
}
else
{
sumOfDays1 = sumOfDays1 + 365;
}
}

for (; year2 != 0; year2--)
{
leapYear2 = 0;
leapYear2 = isLeapYear(year2);
if (leapYear2 == 1)
{
sumOfDays2 = sumOfDays2 + 366;
}
else
{
sumOfDays2 = sumOfDays2 + 365;
}
}

if (sumOfDays1 > sumOfDays2)
{
THEOUTPUT = sumOfDays1 - sumOfDays2;
}
if (sumOfDays1 < sumOfDays2)
{
THEOUTPUT = sumOfDays2 - sumOfDays1;
}

printf("The difference between the two dates is %d days.nn", THEOUTPUT);

}

int displayMenu()
{
int selectionNumber = 0;
printf("DATE SELECTION MENUnn");
printf("1) Convert calendar date into a Julian date.n");
printf("2) Convert Julian date into a calendar date.n");
printf("3) Compute days between two calendar dates.n");
printf("4) Exit program.nn");
printf("ENTER SELECTION (1 - 4):");
scanf("%d", &selectionNumber);
printf("n");
if ((selectionNumber < 1) || (selectionNumber > 4))
{
printf("Error!");
return 4;
}
else
{
return selectionNumber;
}
}

int main(void) {
int year = 0;
int month = 0;
int day = 0;
int julianday = 0;
int selectionNumber = 0;
int secYear = 0;
int secMonth = 0;
int secDay = 0;


while (1)
{
selectionNumber = displayMenu();

if (selectionNumber == 1)
{
printf("Please enter your calender date as follows: MM DD YYYYn");
scanf("%d %d %d", &month, &day, &year);
toJulian(month, day, year);
}
if (selectionNumber == 2)
{
printf("Please enter your julian date with days first, followed by the year.n");
scanf("%d %d",&day, &year);
toCalendar(day, year);
}
if (selectionNumber == 3)
{
printf("Please enter your first calender date as follows: MM DD YYYYn");
scanf("%d %d %d", &month, &day, &year);
printf("Please enter your second calender date as follows: MM DD YYYYn");
scanf("%d %d %d", &secMonth, &secDay, &secYear);
daysBetweenDates(month, day, year, secMonth, secDay, secYear);

}
if (selectionNumber == 4)
{
exit(0);
}
}

}