stamp_t get_stamp(date_t *date);
int get_mins(date_t *start, date_t *end);
int compare(date_t *a, date_t *b);
+int same_day(date_t *a, date_t *b);
int before(date_t *start, int year, int month, int day, int hour, int min);
int all_day(date_t *start, date_t *end);