Filling in a 9x9
You and a friend take turns filling in the unit squares of a 9x9 grid.
The only rule is you can't fill in a square that shares an edge with a square that's already filled in.
The player to fill in the last square wins.
Who has a winning strategy?
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1 solution
Strategy:
The first player goes in the center.
After that he picks the equivalent square to whatever square the other player just picked after a 180 degree rotation about the middle square.