char *months[] = {
   "January", "February", "March", "April", "May",
   "June", "July", "August", "September", "October",
   "November", "December"
};

// Februrary is altered in calp.c if year is a leap year. defaults to 28.
int days_in_month[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

int isleap(int year) {
    return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
}