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Tic-Tac-Toe-Reflect

I assume you know the rules of Tic-Tac-Toe...


Given this Tic-Tac-Toe game-board in progress, can you:

  • Determine who played first?
  • The sequence of moves thus far?
  • What the best next move should be?
  • Who should win the game?


Given this Tic-Tac-Toe game-board with an evident winner, can you:

  • Determine who played first?
  • The sequence of moves thus far?
  • Could the win have been prevented
Extension: With a friend, play a game of Tic-Tac-Toe...but stop after 6 moves. Give the gameboard to another friend to see if they can determine who moved first.

Big Question: Is it possible to find a six-move gameboard where it is impossible to determine who started first?

 


Hint: Jump in...play...and reflect...

 


Solution Commentary: Start with anymove...and say "If this was first play, then..."

Note: You have assume that the moves were made in a "thinking" manner!