Tic-tac-toe

It's a simple tic-tac-toe game with the pseudo AI

How to play?

To play the game you have to use CLI

Select mode by entering special command. Some examples:
- start user user is for 2 human game
- start user easy is for 1 human (plays X's) and 1 easy AI (plays O's) game
- start medium hard is for 2 AI game (medium AI plays X's, hard AI plays O's)
- exit to quit the game
You are free to combine user easy medium hard options, but there should be always only two of them
Make moves by entering the coordinates, for example, 3 1

Notes: the first number stands for a row and the second number stands for a column of the board; numbers start from 1

Easy AI makes random moves
Medium AI only makes considered moves if it's 1 move to win or 1 move to loose, other moves are random
Hard AI always maximizes the utility of the move as far as minimax algorithm is used