Designing A Simple Tic-Tac-Toe Game In Python

In today's discussion, we will create a simple but entertaining two-player game using Python - the classic Tic-Tac-Toe. We'll also examine the principles of game design logic along the way.

Requirements

Before we begin, it's vital to note that the Python version we're using is 3.6. You should have a basic understanding of Python syntax and functions to follow along with the code.

The Game Logic

Tic-Tac-Toe is a very straightforward game. The game board is a 3x3 grid, and the game is played by two players, who take turns. The first player marks moves with a cross 'X', and the second player uses a nought 'O'. The player who has formed a line of three marks wins.

Let's Write The Code

Step 1: Setup The Game Board

Before the exciting coding part, let's understand the board construction. We can represent the game grid using a list in Python, where each element is a space ' ' which will eventually hold a player's move.

board = [' ' for x in range(10)]

Step 2: Function to Insert Letter

Let's create a function to insert the player's plane - 'X' or 'O' on the board at a specific position.

def insert_board(letter, pos):
    board[pos] = letter

Step 3: Function to Check Free Spaces

We need a function to check if any remaining spaces on the board are still empty.

def is_space_free(pos):
    return board[pos] ==  ' '

Step 4: Function to Print the Board

We need to visualize the current game state as we play, so let's write a function that prints out the board on the console.

def print_board(board):
    print('   |   |')
    print(' ' + board[1] + ' | ' + board[2] + ' | ' + board[3])
    print('   |   |')
    print('-----------')
    print('   |   |')
    print(' ' + board[4] + ' | ' + board[5] + ' | ' + board[6])
    print('   |   |')
    print('-----------')
    print('   |   |')
    print(' ' + board[7] + ' | ' + board[8] + ' | ' + board[9])
    print('   |   |')

Step 5: Function to Check Winning Condition

Finally, we need a function that checks if a mark ('X' or 'O') has won.

def is_winner(bo, le):
    return (bo[7] == le and bo[8] == le and bo[9] == le) or (bo[4] == le and bo[5] == le and bo[6] == le) or(bo[1] == le and bo[2] == le and bo[3] == le) or (bo[1] == le and bo[4] == le and bo[7] == le) or (bo[2] == le and bo[5] == le and bo[8] == le) or (bo[3] == le and bo[6] == le and bo[9] == le) or (bo[1] == le and bo[5] == le and bo[9] == le) or (bo[3] == le and bo[5] == le and bo[7] == le)

That's it! You now have the foundation for the Tic-Tac-Toe game in Python. The next steps could involve creating a game flow control, implementing player turns, and refining the terminal interface. Happy coding!