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#1 2011-06-28 22:36:17
how to be unbeatable in tic-tac-toe
it really comes down to a few rules to follow
1st priority
if you have two in a row and the last is open WIN!
2nd priority
if they have two in a row and the last is open BLOCK!
3rd priority (this is the actual unbeatable strategy)
If they go in the corner go in the middle
If they go in the middle go in the corner
If they go on one of the sides go in the middle
If they have two corners and one is open go on one of the sides
PLEASE NOTICE this is unbeatable NOT unTIEable but I do garentee that you will never lose 
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#3 2011-06-29 23:47:22
- LeonardHofstadter
- New Scratcher
- Registered: 2011-06-29
- Posts: 2
Re: how to be unbeatable in tic-tac-toe
Sorry, it's easily beatable (on how hard set to 2, V39, waiting seconds between moves)
Your program doesn't respond to the same initial 2 moves the same each game, but you can beat it about at least 1/3 the time by picking a corner, (program will then take center), then you choose either outside center farthest from the corner you initially chose. After that the Program will sometimes obviously pick the wrong box. You can reproduce it by repeating this sequence a few times on a new game:
Define board:
123
456
789
Start with 7, computer plays 5 , you play 2.
Sometimes computer plays 8 or 9 next, if so you play 1 and force a win on your next move.
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#4 2011-06-30 00:12:30
- LeonardHofstadter
- New Scratcher
- Registered: 2011-06-29
- Posts: 2
Re: how to be unbeatable in tic-tac-toe
... BTW here's a tic-tac-toe I found that is really unbeatable:
http://scratch.mit.edu/projects/fcwang/1803996
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