Answering msg from Paul Edwards to rowan_crowe,
on Monday January 22 1996 at 23:18

 r>> Based on the above, I've written a C callable ASM function to
 r>> decide whether it's a leap year. I'm sure it's been done zillions
 r>> of times in C too, but here's my particular solution.

 PE> Here's the C code I have.  It is unattributed, so I will have
 PE> to dig up another version or write my own or something later
 PE> on...

 PE> #ifndef ISLEAP
 PE> #define ISLEAP
 PE> #define isleap(year) ((((year%4)==0) && ((year%100)!=0)) ||
 PE> ((year%400)==0)) #endif

Cworr! Borland C++ generates almost *exactly* the same hand-written ASM
that I posted. It is a fairly logical evaluation, I guess.

BTW, the algorithm I used says:

LeapYear if Year Mod 4 = 0
   EXCEPT if Year Mod 100 = 0
       UNLESS Year Mod 1000 = 0

I presume the last should actually be 400. Do you have any official
documentation to confirm this? (I seem to remember you posting something
like that some time ago...)

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