Author: Uri Blass
Date: 15:35:57 05/30/04
Go up one level in this thread
On May 30, 2004 at 18:20:15, Peter Fendrich wrote:
>On May 30, 2004 at 18:09:49, Uri Blass wrote:
>
>>On May 30, 2004 at 17:51:13, Peter Fendrich wrote:
>>
>>>If zobrist is signed you will encounter problems when shifting it.
>>>/Peter
>>
>>I think that my zobrist is unsigned.
>>
>>
>>My function to generate "random" 64 bit numbers generate signed number but
>>return it as unsigned number
>>
>>I have
>>typedef unsigned __int64 BitBoard;
>>static BitBoard rand64()
>>{
>> __int64 r = rand();
>> r ^= (__int64)rand() << 15;
>> r ^= (__int64)rand() << 30;
>> r ^= (__int64)rand() << 45;
>> r ^= (__int64)rand() << 60;
>>return r;
>>}
>>
>>BitBoard zobrist[6][2][64];
>>
>>zobrist[fil][i][j]=rand64();
>>
>>The problem is that when I do
>>
>>r1=(unsigned)zobrist[fil][i][j]&4294967295;
>>r2=(unsigned)(zobrist[fil][i][j]>>32);
>>r=r1 | (BitBoard) r2<<32;
>>
>>I get r!=zobrist[fil][i][j]
>>
>>Uri
>
>
>What made me think you have a signed zobrist are the
>rx=(unsigned)zobrist[fil][i][j].... statements. There is no reason to cast to
>unsigned if it's already unsigned.
>The statement:
>r2=(unsigned)(zobrist[fil][i][j]>>32);
>looks very strange to me because with parentheses you force the "(unsigned)"
>cast to be made after the shift is done. It makes no sence to to me whether it's
>signed or not.
>
>/Peter
It seems that the problem is not the zobrist key but the fact that r1 and r2
were regular int
I need to write the conversion to unsigned otherwise I get a warning of losing
information in conversion from 'unsigned __int64' to 'unsigned int
Now it seems that I needs different numbers.
I used the following function to print 32 numbers into the screen and later
copied them into the file.
static BitBoard rand64()
{
__int64 r = rand();
r ^= (__int64)rand() << 15;
r ^= (__int64)rand() << 30;
r ^= (__int64)rand() << 45;
r ^= (__int64)rand() << 60;
printf(" %u ",r);
printf(" %u ",r>>32);
return r;
}
I think that I will print them into the screen not inside BitBoard rand64() but
after I calculate the zob keys and I expect to get different numbers that I will
be able to translate them to the zobrist keys.
Uri
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