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Friday puzzle -- tic-tac-toe plus

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Friday puzzle -- tic-tac-toe plus

#1

Friday puzzle -- tic-tac-toe plus

It's well-known that two skillfull players playing tic-tac-toe will always end in a tie. And it doesn't even mater where the first player plays; it will still end in a tie.

Another game played on a 3x3 grid has each player given three markers, which they alternate putting on the board. After all markers are on the board, they continue alternating turns, moving one of their markers to an adjacent empty position. The first to get three in a row wins.

Assuming skillful players, will the first always win, the second always win, or will it end in a tie, like tic-tac-toe, and what is the strategy?

Below is a diagram of a board. If it is white's turn, he will move 5->6 or 8->9, and black will be unable to block him from winning on the next move. If it is blacks turn, he will move from 1->4, and white will be unable to prevent him from winning on the next turn with 2->1.


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Re: Friday puzzle -- tic-tac-toe plus

#2

Re: Friday puzzle -- tic-tac-toe plus

Interesting game. Looks like the pivotal move is the first one.

Re: Friday puzzle -- tic-tac-toe plus

#3

:-)

To make the game more fun to play, outlaw that pivotal first move. Then the game becomes one of no-win between two skilled players (which was not one of the choices I gave in the original -- no one can win, but neither does it end in a tie, except by mutual agreement)

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