Can You Beat This Game?

https://news.ycombinator.com/item?id=1685145

by integraleq • 16 years ago

2 14 16 years ago

news.ycombinator.com

HN,

git://github.com/inteq/Tic-Tac-Toe.git

I would like to issue a challenge to see if you can find a way to beat my tic-tac-toe program. I would definitely appreciate any feedback that will help me improve the brains of the cpu opponent. It is console driven and not pretty on the outside. Thanks!

mphillips34• 16 years ago

http://en.wikipedia.org/wiki/Tic-tac-toe#Strategy

po4• 16 years ago

It was a bit buggy but I beat the cpu. If you play tic-tac-toe the player who goes first should be able to win or at worst case force a draw. If you go second you should be able to force a draw. With two players who both know how to play an optimal game, you will always have a draw.

Tic-tac-toe is basically a solved game which should make it easy to code.

integraleq6• 16 years ago

Which part did you find buggy? I would like to tighten it up. Thanks!

po4• 16 years ago

All of the squares in the field were labeled with "-1"

    $ python tictactoe.py 
    Enter H or T to decide if you will go first:h
    Enter 'X' or 'O' to select the shape that you want to use:x
    #### Initial Game Board State
    [-1, -1, -1]
    [-1, -1, -1]
    [-1, -1, -1]
    Enter the slot(location) where you want to place your shape:(available slots are :'0', '1', '2', '3', '4', '5', '6', '7', '8'):1
    you have chosen to place an 'X' at 1.
    #### Game Board State After Move By:player
    [-1, 'X', -1]
    [-1, -1, -1]
    [-1, -1, -1]

systemtrigger2• 16 years ago

cracks knuckles

After a few minutes trying different strategies:

If I win the coin toss I'm winning the game, every time. If I lose the coin toss it always ends in a draw.

Transcript (of 7 wins): http://dl.dropbox.com/u/142733/tictactoe.txt

Assuming I win the coin toss, I always choose a corner for my first move. The CPU should then take the center but it never does. This ensures I always win.

That said, great job so far. It's very close to perfect IMO.

integraleq6• 16 years ago

Thanks a ton! I will tighten it up! Hopefully, you will pull the next release and try to beat it again. I do hope it was not a complete pushover.....

integraleq6• 16 years ago

Ok!!! Round 2! Any challengers?

po4• 16 years ago

Also you neglected to mention the most interesting part of this:

http://github.com/RichardBronosky/Tic-Tac-Toe

The forked network for this project is interesting. Is this for a class or something?

integraleq6• 16 years ago

Sorry that I did not mention that part: This was actually for a job interview. So, it had to be completed in a short amount of time.

zbanks• 16 years ago

Tic-tac-toe is proven to be unlosable. (You can win if you go first & you are playing an imperfect opponent)

Check out http://en.wikipedia.org/wiki/Tic-tac-toe#Strategy for the description of the algorithm.

Can You Beat This Game?

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