--- a/date.c Mon Jan 01 19:37:53 2007 +0000
+++ b/date.c Mon Jan 01 22:00:54 2007 +0000
@@ -92,9 +92,22 @@
int rem = date % (365 * 400 + 97);
uint16 x;
- /* There are 24 leap years in 100 years */
- yr += 100 * (rem / (365 * 100 + 24));
- rem = rem % (365 * 100 + 24);
+ if (rem >= 365 * 100 + 25) {
+ /* There are 25 leap years in the first 100 years after
+ * every 400th year, as every 400th year is a leap year */
+ yr += 100;
+ rem -= 365 * 100 + 25;
+
+ /* There are 24 leap years in the next couple of 100 years */
+ yr += 100 * (rem / (365 * 100 + 24));
+ rem = (rem % (365 * 100 + 24));
+ }
+
+ if (!IsLeapYear(yr) && rem >= 365 * 4) {
+ /* The first 4 year of the century are not always a leap year */
+ yr += 4;
+ rem -= 365 * 4;
+ }
/* There is 1 leap year every 4 years */
yr += 4 * (rem / (365 * 4 + 1));