Remember Tic Tac Toe? See Wikipedia if you can't remember the rules, or if you haven't ever played. It involves a couple of players, a simple board, checking for victory in a game loop... all the conditions that make it a fun little problem to solve using our newfound OOP sea legs. Let's build it!
Build a tic-tac-toe game on the command line where two human players can play against each other and the board is displayed in between turns.
1. Think about how you would set up the different elements within the game... What should be a class? Instance variable? Method? A few minutes of thought can save you from wasting an hour of coding.
2. Build your game, taking care to not share information between classes any more than you have to.
3. Post your solution below, then check out [this example solution from RosettaCode.org](http://rosettacode.org/wiki/Tic-tac-toe#Ruby).
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