Comment by pedrocr | Hacker News Reader

Comment by pedrocr | Hacker News Reader

I think I have the beginning of a solution. The end result should be 2048 on the top-right corner (for the explanation). Always keep the highest value there. To do that never do a down without the right column filled and never do a left without the top row filled. Within those restrictions keep the top row in ascending order by building numbers on the left of the second row, so that they will match above and cascade right in powers of two.

I did this successfully for a while and then had no other option but a down without the rightmost column filled and lost my placement.

EDIT: A variation of this that works well is to only do up, left and right if at all possible. This keeps the highest values on top making it easier to match top-down. I've been stuck on 512 though.

The key is to have a well defined 'edge' between filled and empty areas - so that the high-valued tiles are on the corned away from the emptiness where 2s spawn; and low-value tiles are on/near the border.

Note that you can't afford to keep much unconnected duplicates - near the win point, you need to have 1024+512+256+128+64+32+16+8+4+2 which is 9/16 tiles filled already, so a few extra mid-value tiles cut your 'operating space' to near zero; so you must keep the high-values mostly ordered and agressively eliminate unneeded duplicates.

I was able to get 2048 building off of your solution. As you said, always keep your highest number in the top right corner. Try to build the next highest numbers up along the right edge, so that you have say, 256, 128, 64, 32 along the right edge. Always keep 4 numbers there, and only use up/down/right. Then just focus on building whatever number you need next to double the bottom right number, so that you can "chain up" numbers along the right edge and double your highest number in the top right.

Kind of hard to explain in words, but hopefully that helps!

Yep, this is pretty much the same solution with the right edge instead of the top edge. I got to 1024 and then blundered and couldn't get 2048. This thing is addictive though.

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