Forum Archive :
Puzzles
Worst possible checker play
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> Here's a puzzle:
> Based on GNU 2-ply evaluation can you construct the worst possible
> checker play blunder you could make?
This question was done as a contest at GammonLine and the winner (Teppo
Salo) came up with this:
Money session. Score X-O: 0-0
X to play (2 2)
+24-23-22-21-20-19-------18-17-16-15-14-13-+
| O O O O O | | X X X O |
| O O O O O | | |
| | | | S
| | | | n
| | | | o
| |BAR| | w
| | | | i
| | | | e
| | | |
| X X X X X | | |
| X X X X X X | | O O O X O |
+-1--2--3--4--5--6--------7--8--9-10-11-12-+
Pipcount X: 95 O: 107 X-O: 0-0/Money (1)
CubeValue: 2, X owns Cube
Best Move: 14/12*/10*/8*/6
Worst Move: 5/1 4/2 3/1
Gregg C.
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Raccoon writes:
Teppo Salo's solution:
GNU Backgammon Position ID: 22ygVADbtiCSAA
Match ID : UQkJAAAAAAAA
+24-23-22-21-20-19------18-17-16-15-14-13-+ O: O
| O O O O O | | X X X O | 0 points
| O O O O O | | |
| | | |
| | | |
| | | |
| |BAR| |v
| | | |
| | | |
| | | |
| X X X X X | | | Rolled 22
| X X X X X X | | O O O X O | 0 points
+-1--2--3--4--5--6-------7--8--9-10-11-12-+ X: X (Cube: 2)
1. Cubeful 2-ply 14/12*/10*/8*/6 Eq.: +2.2343
215. Cubeful 2-ply 5/1 4/2 3/1 Eq.: -2.3493 ( -4.5835)
Slightly altered, slightly worse:
GNU Backgammon Position ID: tm2gVADbtgCpAA
Match ID : UQkJAAAAAAAA
+24-23-22-21-20-19------18-17-16-15-14-13-+ O: O
| O O O O O | | X X X X O | 0 points
| O O O O O | | |
| | | |
| | | |
| | | |
| |BAR| |v
| | | |
| | | |
| | | |
| X X X X X | | | Rolled 22
| X X X X X X | | O O O O | 0 points
+-1--2--3--4--5--6-------7--8--9-10-11-12-+ X: X (Cube: 2)
1. Cubeful 2-ply 14/12*/10*/8*/6 Eq.: +2.2495
216. Cubeful 2-ply 5/1 4/2 3/1 Eq.: -2.3792 ( -4.6287)
Aim for -5.000 !
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