Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Ultimate Tic Tac Toe

mathwithbaddrawings.com

Post reply on HN
Print view View original

101–110 of 129 posts

Re: Ultimate Tic Tac Toe

#101

Post by matchu »

triangleman83 wrote: post #99
matchu wrote: post #88

Earlier quoted context omitted.

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?

The KA folks were playing this in the office a few weeks back, James wanted to make a good AI for it, spent a weekend or so on it, and discovered the Perfect Bot in the process. My sole contribution to this program (in addition to moral support!) was creating a copy that's set to Perfect Bot by default for y'all's convenience, but his original has all sorts of crazy config.

Re: Ultimate Tic Tac Toe

#102

Post by AUmrysh »

What if you played it where the square selected is the direction you move to go to the next board. If the player selects the center square on a board, that board must be played again. If the player selects the left square, the board to the left must be played next. If a corner square is picked, you play the board to that diagonal direction.

If the corner is not attached to a board, you roll the board around as though the ends are connected (or as though it's an infinitely repeating tiling of the same game). For example, the bottom right square on the bottom right board makes the next board the top left.

The center-right square on the center-right board would result in the next board being the center-left board, and so on.

Would there be a gambit in this ruleset?

edit: So, it looks like the same gambit applies, instead of selecting the center piece you just pick the one pointing toward the center every time.

Re: Ultimate Tic Tac Toe

#104

Post by gojomo »

michaelfeathers wrote: post #10

My favorite "mathematician game" is Sprouts: http://nrich.maths.org/2413 First heard about it in a column in Scientific American by A. K. Dewdney. The rules are simple and it is rather fun. In one of his columns he talked about playing a toroidal version where a line going off one edge of a rectangular page comes back in on the opposite side.

I remember another two-player pen-and-paper game I got from Scientific American long ago... I think it was called 'Loops'.

• the board is first built by each player alternating in drawing an oval lightly (as with pencil) until 5 ovals are placed; each oval after the first must intersect another in at least one place, such as a tangent, but usually more

• every intersection gets a dot to emphasize its role as a vertex; the oval segments between them are edges

• after the board is built, one player starts by picking any vertex, and tracing (heavily or with a unique pen color) an edge from that point to a new vertex, and then to another vertex, and then to another (3 segments end-to-end per turn)

• the next player starts from the vertex where the previous player ended; if for any of their 3 segments (including the 1st) there is no legal move, their turn ends and the other player has choice of vertex to begin their next move

• if a player's move completes a loop, they capture it (adding their initials inside); first to capture 3 loops wins

So for example, the 5-rings olympic logo is a legal board (though one which allows the 1st player to immediately capture a 2-segment oval on either end).

Anyone else play this? Do I remember the name right?

Re: Ultimate Tic Tac Toe

#105

Post by tensaix2j »

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…

Does the AI always have to make the first move?

Re: Ultimate Tic Tac Toe

#107

Post by [deleted] »

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…

[deleted]

Re: Ultimate Tic Tac Toe

#108

Post by gcb0 »

tensaix2j wrote: post #105
matchu wrote: post #88

Earlier quoted context omitted.

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…

Does the AI always have to make the first move?

Technically a game of tic tac toe is comprised of two matches, one each player starting

Re: Ultimate Tic Tac Toe

#109

Post by matchu »

tensaix2j wrote: post #105
matchu wrote: post #88

Earlier quoted context omitted.

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…

Does the AI always have to make the first move?

For Perfect Bot's strategy to work, yeah, but the environment is very open to configuration. Set xIsComputer to false and yIsComputer to "monte" for a fun challenge in which you go first.

Re: Ultimate Tic Tac Toe

#110

Post by [deleted] »

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…

[deleted]
Post reply on HN