Python code for Tic-Tac-Toe Game

Posted On February 11, 2023

Tic Tac Toe is a two-player paper-and-pencil game. The game is played on a 3×3 grid, and the goal is to place three of your symbols (usually “X” or “O”) in a row, either horizontally, vertically, or diagonally, before your opponent does the same. If all the spaces on the grid are filled and neither player has achieved three in a row, the game is considered a draw.

Code for Tic-Tac-Toe

board = [" " for x in range(9)]

def print_board():
    row1 = "| {} | {} | {} |".format(board[0], board[1], board[2])
    row2 = "| {} | {} | {} |".format(board[3], board[4], board[5])
    row3 = "| {} | {} | {} |".format(board[6], board[7], board[8])

    print()
    print(row1)
    print(row2)
    print(row3)
    print()

def player_move(icon):
    if icon == "X":
        number = 1
    elif icon == "O":
        number = 2
    print("Your turn player {}".format(number))
    choice = int(input("Enter your move (1-9): ").strip())
    if board[choice - 1] == " ":
        board[choice - 1] = icon
    else:
        print()
        print("That space is already taken!")

def is_victory(icon):
    if (board[0] == icon and board[1] == icon and board[2] == icon) or \
       (board[3] == icon and board[4] == icon and board[5] == icon) or \
       (board[6] == icon and board[7] == icon and board[8] == icon) or \
       (board[0] == icon and board[3] == icon and board[6] == icon) or \
       (board[1] == icon and board[4] == icon and board[7] == icon) or \
       (board[2] == icon and board[5] == icon and board[8] == icon) or \
       (board[0] == icon and board[4] == icon and board[8] == icon) or \
       (board[2] == icon and board[4] == icon and board[6] == icon):
        return True
    else:
        return False

def is_draw():
    if " " not in board:
        return True
    else:
        return False

while True:
    print_board()
    player_move("X")
    print_board()
    if is_victory("X"):
        print("X wins! Congratulations!")
        break
    elif is_draw():
        print("It's a draw!")
        break
    player_move("O")
    if is_victory("O"):
        print_board()
        print("O wins! Congratulations!")
        break
    elif is_draw():
        print("It's a draw!")
        break

In this code, the game board is represented by a list of 9 spaces. The print_board function formats the board and displays it to the console. The player_move function allows the player to make a move by entering a number between 1 and 9, which corresponds to the positions on the board. The is_victory function checks if a player has won by matching the icon with 3 consecutive spaces in a row, column, or diagonal. The is_draw function checks if the game has ended in a draw

Explanation of Code

The code implements the Tic Tac Toe game using a list called board that represents the 3×3 game board. The board is initialized with 9 spaces represented as empty strings. The print_board function formats the board and displays it to the console. The player_move function allows the player to make a move by entering a number between 1 and 9, which corresponds to the positions on the board. The is_victory function checks if a player has won by matching the icon with 3 consecutive spaces in a row, column, or diagonal. The is_draw function checks if the game has ended in a draw.

Unit Test

import unittest

class TestTicTacToe(unittest.TestCase):
    def test_print_board(self):
        board = ["X", "O", "X", "X", "O", " ", " ", " ", " "]
        expected_output = "| X | O | X |\n| X | O |   |\n|   |   |   |\n"
        self.assertEqual(print_board(board), expected_output)

    def test_player_move(self):
        board = [" ", " ", " ", " ", " ", " ", " ", " ", " "]
        player_move("X", board)
        self.assertEqual(board, ["X", " ", " ", " ", " ", " ", " ", " ", " "])

    def test_is_victory(self):
        board = ["X", "X", "X", " ", " ", " ", " ", " ", " "]
        self.assertTrue(is_victory("X", board))

    def test_is_draw(self):
        board = ["X", "O", "X", "X", "O", "O", "O", "X", "X"]
        self.assertTrue(is_draw(board))

if __name__ == "__main__":
    unittest.main()

GUI for the program

import tkinter as tk

class TicTacToe(tk.Tk):
    def __init__(self, *args, **kwargs):
        tk.Tk.__init__(self, *args, **kwargs)
        self.title("Tic Tac Toe")
        self.geometry("300x325")
        self.board = [" " for x in range(9)]
        self.buttons = []
        for i in range(9):
            button = tk.Button(self, text=" ", font=("Helvetica", 24), width=3, height=1,
                               command=lambda i=i: self.button_click(i))
            button.grid(row=i//3, column=i%3)
            self