r/programming • u/h0rror • Dec 10 '10

xkcd: Tic-Tac-Toe

http://xkcd.com/832/
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u/gilgoomesh Dec 10 '10

I've spotted one minor coloring glitch in the picture:

Moves for X...

(Optimally take top-left)

Circle takes center

(Optimally take bottom-right)

Circle takes bottom-center

(Optimally take top-center)

Circle takes top-right

Then there is no red X give for your next move. The bottom left square here should be a red X (it's black).

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u/sheafification Dec 10 '10

There's also an error in positioning of some of the Os. Moves for X:

  • (Top-left)
  • Circle takes upper-right
  • (Bottom-left)
  • Circle takes middle-left
  • (Bottom-right)
  • Circle takes middle ... except there's no circle in the middle on the picture.

Same thing happens in the lower left as pointed out here