im trying to convert julian date to calendar date and vice versa
im not getting any errors, but the output im getting is ridiculous.

any help is appreciated

#include "stdafx.h"

/*
int _tmain(int argc, _TCHAR* argv[])
{
return 0;
}
*/

int isLeapYear(int year){
  return ((!(year % 4) && year % 100) || !(year % 400));
}

int getChoice(void)
{
	int result = 1;
  scanf_s("%d", &result);

  return result;
}

int sum_array(int dayspermonth[], int n);

void getCalendarDate(int *month, int *day, int *year)
{
  // Input from console month day year
  int m, d, y;
  scanf_s("%d %d %d", &m, &d, &y);
  *month = m;
  *day = d;
  *year = y;
}

void calendarToJulian(void)
{
  int m, d, y;
  // Array indices      0,   1, 2, ...
  int dayspermonth[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
  int sum;
  int i; // Loop index
  getCalendarDate(&m,&d,&y);

  // if (m = 5) // Is month May?  Error = is assignment
  // if (m == 5) // Is month May?  Equivalent test good

  // m - 1 translates human counting to an array index
  
    
    
    // Start out with summing the days and then add a leap year day
    sum = 0; 

    for (i = 0; i < (m - 1); i++)  
    {
      // sum = sum + dayspermonth[i];
      sum += dayspermonth[i] + d;
	  }
	
	for (i = 1; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
	if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 2; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 3; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 4; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 5; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 6; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 7; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 8; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 9; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 10; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }
	for (i = 11; i < (m - 1); i++)
	{ sum += dayspermonth[i] + d;
	}
    if (isLeapYear(y))
    {
      sum++;
    }

}
void getJulianDate(int *julianDay, int *year)
{
	int y, jd;
  // Input from console month day year
   scanf_s("%d %d", &jd, &y);
  *julianDay = jd;
  *year = y;
  }
void julianToCalendar(void)
{
	int m, y, jd, d;
	 int totalToSub;
	int dayspermonth[] = {31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365}; 
	int i; // Loop index

	getJulianDate(&jd,&y);

  
  for (i = 0; i < 11; i++)
  {totalToSub = dayspermonth[i];
  }
  if (i >= 1) 
    {
	 // This is Feb, check for leap year
      if (isLeapYear(y))  {
        totalToSub++;
      }
    }

    // if ((julianDay - dayspermonth[i]) > 0)
    if ((jd - totalToSub) > 0)
    { m = i + 1;
	d = jd - totalToSub;
	y = y;
      // positive, past the given month
    }
    else ((jd - totalToSub) < 0);
    { m = i - 1;
	d = jd - totalToSub;
	y = y;
      // number is negative, i - 1 is the month we are currently within
    }
} 



FILE *csis;

int main(void) {
void menu(void);
int choice;
fopen_s(&csis, "csis.dat", "w");
  printf("Date Selection Menu\n");
  printf("1) Calendar to Julian\n");
  printf("2) Julian to Calendar\n");
  printf("3) Exit\n");
  printf("Enter Selection (1 - 3)\n");
	
   do {
    choice = getChoice();
    switch (choice) {
	case 1 : calendarToJulian();
		printf("Julian day: %d %d\n", calendarToJulian); break;
    case 2 : julianToCalendar(); 
		printf("Calendar day: %d %d %d\n", julianToCalendar); break;
	case 3 : break;
		}
	 }
  while (choice !=3);
  return 0;
}

Care to elaborate, or do you really want us to search through 200 lines of code not knowing what we're looking for? When asking for help, details are important.

I think there is something wrong with this part

do {    
choice = getChoice();    
switch (choice) {	
case 1 : calendarToJulian();		
printf("Julian day: %d %d\n", [U]calendarToJulian[/U]); break;    
case 2 : julianToCalendar(); 		
printf("Calendar day: %d %d %d\n", [U]julianToCalendar[/U]); break;	
case 3 : break;		
}	 
}

The underlined variables aren't defined as integers, but if I change it to "jd(julianday), y (year)" and declare and define those I get errors. So Im not sure where to go witht that

calendarToJulian) is not a variable, it's a function. The ending ) is a big problem.
You call the function but return nothing. Then you call the function wrong a seconf time. Why? Call the function and return the answer. Then use the answer in the output line.

what do you mean by "return the answer?"

return value;
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