Tic Tac Toe

An adversarial game.

Prerequisites

• Anaconda 3.7+
• Python 3.7+
• Pip

Setup

Optionally fork this remote repository, to create a copy under your own control. Then "clone" or download the remote repository (or your forked copy) onto your local computer, for example to your Desktop. Then navigate to wherever you downloaded the repo:

cd ~/Desktop/tic-tac-toe-py

Create a virtual environment:

conda create -n tictactoe-env python=3.8

Activate the virtual environment:

conda activate tictactoe-env

Install package dependencies within the virtual environment:

pip install -r requirements.txt

Player Types

When you play games, you'll be able to select any of the following combinations of players:

player type(s)	description
HUMAN	A human player who will input their selections.
COMPUTER-EASY or RANDOM	A computer player which makes random selections. Easy to beat.
COMPUTER-HARD or MINIMAX	A computer player which thinks ahead to make optimal selections. Uses the "minimax" algorithm to simulate moves and evaluate all possible game states. Impossible to beat.
MINIMAX-AB	A much faster version of the hard computer player. Uses "alpha-beta" pruning to skip evaluations of unnecessary game states.

Usage

Game Play

Play a game (human vs human, human vs computer, computer vs computer):

python -m app.game

Game Simulation

Play many games (computer vs computer), saves results to CSV file in "data" directory. Optionally pass the game count and/or player strategies as environment variables:

python -m app.jobs.play_games

# alternatively:
GAME_COUNT=3 python -m app.jobs.play_games

# alternatively:
X_STRATEGY="COMPUTER-HARD" O_STRATEGY="COMPUTER-EASY" GAME_COUNT=100 python -m app.jobs.play_games

Testing

Run automated tests, to know whether the app is working as expected:

pytest

Demo

Here is a demonstration of gameplay between computer players:

SELECT X PLAYER TYPE ('HUMAN' / 'COMPUTER-EASY' / 'COMPUTER-HARD'): COMPUTER-HARD
SELECT O PLAYER TYPE ('HUMAN' / 'COMPUTER-EASY' / 'COMPUTER-HARD'): COMPUTER-HARD
Would you like to use a pre-saved game state? (Y/N): n

                A   B   C

            1     |   |
               -----------
            2     |   |
               -----------
            3     |   |


PLAYER X THINKING...

                A   B   C

            1     |   |
               -----------
            2     |   |
               -----------
            3   X |   |


PLAYER O THINKING...
... <Square A1> -3
... <Square B1> -3
... <Square C1> -3
... <Square A2> -3
... <Square B2> 0
... <Square C2> -3
... <Square B3> -3
... <Square C3> -3

                A   B   C

            1     |   |
               -----------
            2     | O |
               -----------
            3   X |   |


PLAYER X THINKING...
... <Square A1> 0
... <Square B1> 0
... <Square C1> 0
... <Square A2> 0
... <Square C2> 0
... <Square B3> 0
... <Square C3> 0

                A   B   C

            1   X |   |
               -----------
            2     | O |
               -----------
            3   X |   |


PLAYER O THINKING...
... <Square B1> -5
... <Square C1> -5
... <Square A2> 0
... <Square C2> -5
... <Square B3> -5
... <Square C3> -5

                A   B   C

            1   X |   |
               -----------
            2   O | O |
               -----------
            3   X |   |


PLAYER X THINKING...
... <Square B1> -4
... <Square C1> -4
... <Square C2> 0
... <Square B3> -4
... <Square C3> -4

                A   B   C

            1   X |   |
               -----------
            2   O | O | X
               -----------
            3   X |   |


PLAYER O THINKING...
... <Square B1> 0
... <Square C1> 0
... <Square B3> 0
... <Square C3> 0

                A   B   C

            1   X | O |
               -----------
            2   O | O | X
               -----------
            3   X |   |


PLAYER X THINKING...
... <Square C1> -2
... <Square B3> 0
... <Square C3> -2

                A   B   C

            1   X | O |
               -----------
            2   O | O | X
               -----------
            3   X | X |


PLAYER O THINKING...
... <Square C1> -1
... <Square C3> 0

                A   B   C

            1   X | O |
               -----------
            2   O | O | X
               -----------
            3   X | X | O


PLAYER X THINKING...
... <Square C1> 0

                A   B   C

            1   X | O | X
               -----------
            2   O | O | X
               -----------
            3   X | X | O


{'winner': None, 'reason': 'NO_MORE_SQUARES', 'message': 'TIE GAME'}

License