Implement a console-based Tic-Tac-Toe game played on the console.
Define 4 constants — one for the board size, one for an empty cell, one representing a user play and one representing a computer play.
You should define methods to do at least the following (probably more!):
- Clear board
- Get the user to play
- Get the computer to play
- Check to see if the game is over
- Display the board
- Find out who won