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Subject: Something funny that happened to me

Author: Edward Seid

Date: 17:09:29 10/10/03


I've been working on a solution to the Pawn Game.

Using only negamax with alpha-beta pruning (no transposition tables yet), I've
been able to solve the 6 vs 6 pawn game.  It took about 1 hour and 1 billion
nodes.  I was curious to see if my rudimentary algorithm would be able to find
the solution to the 7 vs 7 pawn game.  So I set up the following position and
let my AMD 1900+ loose on it.

[D]8/ppppppp1/8/8/8/8/PPPPPPP1/8 w - -
Guess what happened after 105 TRILLION nodes and many days?
OutOfBoundsException!

When generating moves, my moveList array has an upperbound of 15, allowing for
16 possible moves.

After the moves
1. d4  d5
2. e4  dxe4
3. d5  a5
4. b3  a4
5. f3  axb3
6. d6

the position becomes
[D]8/1pp1ppp1/3P4/8/4p3/1p3P2/P1P3P1/8 b - -
and Black has 17 possible moves.  I guess I shouldn't be so cheap with my array
space :(



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