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Ultimate Tic Tac Toe

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Re: Ultimate Tic Tac Toe

#91

Post by jjcm »

The one I play with my friends is usually a 4-in-a-row, 4 level board. You can win on any individual level, or by creating a straight line of 4 that intersects plays on each level (so playing in the top right of each level would net you a win, for instance). It forces the players to keep a three dimensional model in their head and opens up the board for more counters/strategy.

Anyone care for a game?

    level 1    level 2    level 3    level 4
    .|.|.|.    .|.|.|.    .|.|.|.    .|.|.|.
    .|.|.|.    .|.|.|.    .|.|.|.    .|.|.|.
    .|.|.|.    .|.|.|.    .|.|.|.    .|.|.|.
    .|.|.|.    .|.|.|.    .|.|.|.    .|.|.|.

Re: Ultimate Tic Tac Toe

#93

Post by PebblesRox »

3pt14159 wrote: post #36
jbri wrote: post #30

Earlier quoted context omitted.

Instead of filling the center square on the last board, you can fill the corresponding square and then start forcing your opponent to win that board.

Doesn't quite work, since the opponent can chose the centre square which leaves you with a free move, but whatever master square you place your free move in, can no longer be used to force him back into the same master square.

Why not? All the other squares are empty except for their centers. You can put your opponent wherever you want.

Re: Ultimate Tic Tac Toe

#94

Post by PebblesRox »

homonculus wrote: post #64
3pt14159 wrote: post #36

Earlier quoted context omitted.

Doesn't quite work, since the opponent can chose the centre square which leaves you with a free move, but whatever master square you place your free move in, can no longer be used to force him back into the same master square.

The opponent can't choose the center square because you've already filled them all in the initial phase of the gambit.

"Instead of filling in the center square on the last board..."

Re: Ultimate Tic Tac Toe

#95

Post by gohrt »

lotharbot wrote: post #76
shardling wrote: post #61

A weird version of tic-tac-toe my friends and I came up with years ago: you play without a board. Any move is valid so long as you could superimpose a standard tic-tac-toe grid over the results. (You assume the marks are at the center of their respective squares; you allow the board to be at any scale or angle, but you can't skew it.) The first two moves have no constraint, so you can just start with an X and O alrea…

Somebody posted another tic tac toe variant on HN some time ago, where the squares were numbered 1-9 and the goal was to get any three squares that summed to 15. It turns out this is equivalent to playing tic tac toe with sides that wrap around (like a torus).

also equivalent to covering every row and column on the board.

Re: Ultimate Tic Tac Toe

#96

Post by nkoren »

matchu wrote: post #88
quesera wrote: post #23

I think the Orwin gambit can be extended to win the game every time. - Force opponent to fill center miniboard, as he describes. - Force opponent to fill (e.g.) northeast corner in the same way. Opponent now has taken two miniboards, and you have none, but you are one turn away from taking each of the remaining seven. - Pick SW corner of SW corner. You have taken SW corner miniboard. Opponent is forced to play in sam…

Here's an implementation that pretty much does exactly that. If someone can beat this bot, lemme know: https://www.khanacademy.org/cs/in-tic-tac-toe-ception-perfec... And here's James Irwin's original implementation, auto-set to a Monte-Carlo AI and with a rules variation that (to my knowledge) prevents Perfect Bot from winning. Play with the config variables at the top for some other AIs and 2-player games and whatn…

The first one is beatable if -- and only if, I believe -- a square with two three-in-a-rows in it counts as both an X and an O. If this is the case, then O can win one round before X has a chance to it. But otherwise -- as you have it configured, where the first to get a three-in-a-row sets the larger square to either an X or an O -- it's unbeatable.

Re: Ultimate Tic Tac Toe

#97

Post by Houshalter »

triangleman83 wrote: post #56
3pt14159 wrote: post #54

Earlier quoted context omitted.

What if o took the centre of the board?

Then according to the rules, X gets to move anywhere. Pick another corner board, make a move in the NW corner, which forces them back to the NW board. Then their best option is to move in the same square of the board you just came from, since you won't be able to send them back to the NW board again. In that case, you move in the same corner as the board you are in, forcing their reply to the same board you're playin…

After that it's pretty easy to force a win. Whatever square they send you to, you just send them back to one of those two squares.

Re: Ultimate Tic Tac Toe

#98

Post by akincisor »

frogpelt wrote: post #45

There's a way to prevent the Orlin gambit. Allow the player with the last three in row to take another turn. This creates a means of alternating who goes first. I'm not sure whether this gives too much advantage to the other player or not.

It does. He can now force you to now place pointless moves in the center square.

Re: Ultimate Tic Tac Toe

#99

Post by triangleman83 »

matchu wrote: post #88
quesera wrote: post #23

I think the Orwin gambit can be extended to win the game every time. - Force opponent to fill center miniboard, as he describes. - Force opponent to fill (e.g.) northeast corner in the same way. Opponent now has taken two miniboards, and you have none, but you are one turn away from taking each of the remaining seven. - Pick SW corner of SW corner. You have taken SW corner miniboard. Opponent is forced to play in sam…

Here's an implementation that pretty much does exactly that. If someone can beat this bot, lemme know: https://www.khanacademy.org/cs/in-tic-tac-toe-ception-perfec... And here's James Irwin's original implementation, auto-set to a Monte-Carlo AI and with a rules variation that (to my knowledge) prevents Perfect Bot from winning. Play with the config variables at the top for some other AIs and 2-player games and whatn…

Yep I don't see any way of beating that bot. You whipped that up just today?
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