2048

Go implementation of 2048 game

Sample

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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       2       |
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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       2       |
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-----------------------------------------------------------------

d

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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       2       |       0       |
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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       4       |
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-----------------------------------------------------------------

r

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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       2       |       2       |
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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       4       |
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-----------------------------------------------------------------

r

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|       2       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       4       |
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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       4       |
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-----------------------------------------------------------------

d

-----------------------------------------------------------------
|               |               |               |               |
|       0       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       0       |
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|       0       |       0       |       0       |       2       |
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|       2       |       0       |       0       |       8       |
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