kuzminsk at taussky.cs.colorado.edu
Tue Oct 28 06:42:29 EST 1997
Joseph Fisk <joe at rm405n-a.roberts.fit.edu> wrote:
] > But if each board takes 200 bits to store, that's tens of thousands
] > of terabytes. How do they do it? Is there a computer chess programmer
] > in the house?
] You could store each possiblity (every single combination wouldn't have to
] be stored; those that lead immediately to checkmate, for example =) as
] only a few bits describing the change from the previous state. Also
] (6*10^14)*200bits = 15000000000000000 terabytes. =)
Hm, 6 * 10^14 * 200 is 1.2 * 10^17 bits, which is 1.5 * 10^16 bytes,
which is about 1.5 * 10^13 KB, or 1.5 * 10^10 MB, or 1.5 * 10^7 GB, or
1.5 * 10^4 TB: tens of thousands of terabytes.
] There is bound to be a lot of repition there; zip would probably take it
] down significantly although obviously that many terabytes is pretty
] extreme. hehehe..
Agreed, there is a lot of redundancy in the 10-ply search tree
Note that while it takes about 200 bits to describe a board, it takes
no more than 9 bits to describe a move, and often less: 4 or less bits
to name the piece, and then 5 or less bits to name the destination
square. Transmitting large search trees trees thus takes only 1/20 of
the bandwidth if you submit moves (think of them as diffs!) instead of
To unsubscribe, send email to majordomo at llamas.net with 'unsubscribe rc5' in the body.
More information about the rc5