
Can AI beat 2048? - ivstitia
http://www.ranjaykrishna.com/1/post/2014/12/can-an-artificial-intelligence-win-2048.html
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maaaats
I'm TA for an AI course at my university. They recently had to deliver and
demonstrate their system beating 2048. Most people used min/max with alpha-
beta pruning, and considered all possible moves and all possible placements of
a 2 or 4 tile. This can make your bot a bit too cautious, so some used
Expectimax instead, weighting each value with the probability of it happening.

Those who had simpler heuristics did better. Trying to combine 4-5 heuristics
is hard, as you have to weight them against each other. The "gradients"
mentioned here did alone produce good results for most students. Of the ~50
people, most managed to demonstrate to me that they could get a 2048 tile
within a time limit. Some even 8k and 16k tiles.

I think most of them got the "Tetris-effect" by watching their bot play a few
rounds, tweak, run it again etc. for a few days. Probably watched blocks
sliding around when making food etc. :p

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marcofiset
In my case it actually lost, but by watching it play I can tell it made very
questionnable decisions about some moves, and it plays a lot less defensively
than I usually do. It managed to get really far, only a couple of moves away
from winning. It actually had assembled every piece for winning, only it
failed to group them together to achieve 2048. Pretty incredible!

Also a very interesting read.

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ranjaykrishna
Thanks for reading the post. :)

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Jeremy1026
As the write up says, this is way more addictive. I'm cheering it along every
move it makes.

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rikacomet
The brilliance of this post is not in the fact that a AI program can beat
another AI program, but if a human conceivable algorithm of this length can
beat the raw cognitive power of human users itself. I would be seriously
diggin this.

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ascotan
I let the algorithm run to the end. 78992 points. Not only did I win I got a
4096 square (which is black btw) and another 2048 square. It died very close
to getting an 8192 square.

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benny
Rly like that game too, did you try it with alpha beta pruning? should
considerably speed up the "look into the future" thing compared to simple
min/max

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ranjaykrishna
Agreed. Another way to optimize it is by running the animations and the AI on
separate threads. The deeper the search tree, the better the AI performs,
irrespective of the heuristic used.

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nkantar
I got way too hooked on the game but never actually managed to beat it. This
makes me wonder whether I could write something that _could_ faster.

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justhw
[https://ov3y.github.io/2048-AI/](https://ov3y.github.io/2048-AI/)

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wazdee
Someone should benchmark these against each other

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uberneo
This looks cool.. I have the same addiction .. whats the max score you have
reached? by urself and by AI?

