A computer science professor encourages his students to break Sudoku's rules

In Sudokill, two players alternate moves that consist of replacing a blank by a number. The first player is called the row player and the second is the column player. Initially, the row player can make any legal Sudoku move. Subsequently, the column player must move in the same column as the last move of the row player and the row player must move in the same row as the last move of the column player. If a player makes an illegal Sudoku move, even by accident, then that player loses.

If we represent blanks as 0s or letters and the row player moves where there is an x:

0 0 6 0 0 0 0 0 0 8 4 0 3 x 2 0 0 0 3 2 0 0 0 5 0 7 4 0 6 0 0 9 0 8 0 0 0 0 0 6 2 4 0 0 0 0 0 2 0 3 0 0 6 0 2 1 0 9 0 0 0 8 7 0 0 0 4 0 3 0 2 5 0 0 0 0 0 0 1 0 0

The the column player must replace a blank in the same column (marked with y's):

0 0 6 0 y 0 0 0 0 8 4 0 3 x 2 0 0 0 3 2 0 0 y 5 0 7 4 0 6 0 0 9 0 8 0 0 0 0 0 6 2 4 0 0 0 0 0 2 0 3 0 0 6 0 2 1 0 9 y 0 0 8 7 0 0 0 4 y 3 0 2 5 0 0 0 0 y 0 1 0 0

Suppose the column player chooses the one marked by an upper case Y:

0 0 6 0 y 0 0 0 0 8 4 0 3 x 2 0 0 0 3 2 0 0 y 5 0 7 4 0 6 0 0 9 0 8 0 0 0 0 0 6 2 4 0 0 0 0 0 2 0 3 0 0 6 0 2 1 0 9 y 0 0 8 7 0 0 0 4 Y 3 0 2 5 0 0 0 0 y 0 1 0 0

The row player must then move in one of the positions marked with a z:
0 0 6 0 y 0 0 0 0 8 4 0 3 x 2 0 0 0 3 2 0 0 y 5 0 7 4 0 6 0 0 9 0 8 0 0 0 0 0 6 2 4 0 0 0 0 0 2 0 3 0 0 6 0 2 1 0 9 y 0 0 8 7 z z z 4 Y 3 z 2 5 0 0 0 0 y 0 1 0 0

Toward the end of the game, the following rules prove important: If there are no blanks in the column where the row player last moved, then the column player may move anywhere. Likewise, if there are no blanks in the row where the column player last moved, the row player may move anywhere.

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1. 1. alphachapmtl 12:04 PM 5/13/09

WShy so many pages? It's annoying!

2. 2. alphachapmtl 12:06 PM 5/13/09

unable to view article...

3. 3. milk 02:09 PM 5/13/09

4. 4. TTLG 11:44 PM 5/13/09

So the idea is to change a game of personal achievement into one of aggression against someone else? Wonderful. Like we don't have enough of those already.

5. 5. flakwack 02:48 PM 5/20/09

WHY would you use 0 and not leave the squares blank? Also, sudoku puzzles are typically square.

6. 6. Bigems 09:02 AM 5/22/09

why not use images instead of plain text! it's 2009 for petes sake

7. 7. acr 12:41 PM 5/22/09

Awkward for students and readers alike.

8. 8. Mirfy 12:53 PM 5/22/09

I liked the idea... a simple game with simple rules that creates a great challenge.

Congratulations !

9. 9. capissen 12:29 PM 5/23/09

Oh yeah, I use sudo kill every time one of my applications starts acting up!

10. 10. dmmiller2k 09:57 AM 7/2/09

Please post the text (non-HTML) version of this article, in one piece. The formatting detracts from the examples and makes them impossible to follow.

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