Python code tic tac toe game: Let\'s use what you\'ve learned about drawing meth

Question

Python code tic tac toe game:

Let's use what you've learned about drawing methods to create a simple tic-tac-toe game.

The game rules are simple:

- players take turns marking cells in a 3 x 3 grid with either X's or O's

- As soon as all cells in a row, column, or diagonal are marked by the same player, that player wins and the game is over.

So your task is to:

create a graphic window with a 3 x 3 grid,

allow players to mark an empty cell by clicking within it

place an X or O in the center of the selected cell (you can assume players alternate turns)

when a player has won (according to the above rules), draw a line through the winning row, column, or diagonal cells

Hint:

You can use a counter variable and a while loop to get mouse clicks until all cells are filled or a player wins,

You can compare the x & y coordinates of each mouse click against coords of grid lines to determine the row and column selected. Because cells are equal size, you know the x coordinate for each vertical line, and the y coordinate for each horizonal line.

You'll need some data structure to track which cells have been marked and by which player. A 2-dimensional list may be most convenient, since it can match the rows and columns of your game. The below code creates a 3x3 list pre-filled with -1 for each item, to indicate the item hasn't been selected yet:

Items in a 2-dimensional list can be accessed by index, just like 1-d list items:

If you don't have the textbook, a full list of graphics.py methods is available at:
https://github.com/MrAlex6204/Books/blob/master/Python%20Programming-An%20Introduction%20to%20Computer%20Science%202nd%20edition-John%20Zelle%202010.pdf (Links to an external site.)

Please upload .py file or use word, pdf ...

Explanation / Answer

# Tic Tac Toe
import random
def drawBoard(board):
# This function prints out the board that it was passed.
# "board" is a list of 10 strings representing the board (ignore index 0)
print(' | |')
print(' ' + board[7] + ' | ' + board[8] + ' | ' + board[9])
print(' | |')
print('-----------')
print(' | |')
print(' ' + board[4] + ' | ' + board[5] + ' | ' + board[6])
print(' | |')
print('-----------')
print(' | |')
print(' ' + board[1] + ' | ' + board[2] + ' | ' + board[3])
print(' | |')

def inputPlayerLetter():
# Lets the player type which letter they want to be.
# Returns a list with the player’s letter as the first item, and the computer's letter as the second.
letter = ''
while not (letter == 'X' or letter == 'O'):
print('Do you want to be X or O?')
letter = input().upper()

# the first element in the list is the player’s letter, the second is the computer's letter.
if letter == 'X':
return ['X', 'O']
else:
return ['O', 'X']

def whoGoesFirst():
# Randomly choose the player who goes first.
if random.randint(0, 1) == 0:
return 'computer'
else:
return 'player'

def playAgain():
# This function returns True if the player wants to play again, otherwise it returns False.
print('Do you want to play again? (yes or no)')
return input().lower().startswith('y')

def makeMove(board, letter, move):
board[move] = letter

def isWinner(bo, le):
# Given a board and a player’s letter, this function returns True if that player has won.
# We use bo instead of board and le instead of letter so we don’t have to type as much.
return ((bo[7] == le and bo[8] == le and bo[9] == le) or # across the top
(bo[4] == le and bo[5] == le and bo[6] == le) or # across the middle
(bo[1] == le and bo[2] == le and bo[3] == le) or # across the bottom
(bo[7] == le and bo[4] == le and bo[1] == le) or # down the left side
(bo[8] == le and bo[5] == le and bo[2] == le) or # down the middle
(bo[9] == le and bo[6] == le and bo[3] == le) or # down the right side
(bo[7] == le and bo[5] == le and bo[3] == le) or # diagonal
(bo[9] == le and bo[5] == le and bo[1] == le)) # diagonal

def getBoardCopy(board):
# Make a duplicate of the board list and return it the duplicate.
dupeBoard = []

for i in board:
dupeBoard.append(i)

return dupeBoard

def isSpaceFree(board, move):
# Return true if the passed move is free on the passed board.
return board[move] == ' '

def getPlayerMove(board):
# Let the player type in their move.
move = ' '
while move not in '1 2 3 4 5 6 7 8 9'.split() or not isSpaceFree(board, int(move)):
print('What is your next move? (1-9)')
move = input()
return int(move)

def chooseRandomMoveFromList(board, movesList):
# Returns a valid move from the passed list on the passed board.
# Returns None if there is no valid move.
possibleMoves = []
for i in movesList:
if isSpaceFree(board, i):
possibleMoves.append(i)

if len(possibleMoves) != 0:
return random.choice(possibleMoves)
else:
return None

def getComputerMove(board, computerLetter):
# Given a board and the computer's letter, determine where to move and return that move.
if computerLetter == 'X':
playerLetter = 'O'
else:
playerLetter = 'X'

# Here is our algorithm for our Tic Tac Toe AI:
# First, check if we can win in the next move
for i in range(1, 10):
copy = getBoardCopy(board)
if isSpaceFree(copy, i):
makeMove(copy, computerLetter, i)
if isWinner(copy, computerLetter):
return i

# Check if the player could win on their next move, and block them.
for i in range(1, 10):
copy = getBoardCopy(board)
if isSpaceFree(copy, i):
makeMove(copy, playerLetter, i)
if isWinner(copy, playerLetter):
return i

# Try to take one of the corners, if they are free.
move = chooseRandomMoveFromList(board, [1, 3, 7, 9])
if move != None:
return move

# Try to take the center, if it is free.
if isSpaceFree(board, 5):
return 5

# Move on one of the sides.
return chooseRandomMoveFromList(board, [2, 4, 6, 8])

def isBoardFull(board):
# Return True if every space on the board has been taken. Otherwise return False.
for i in range(1, 10):
if isSpaceFree(board, i):
return False
return True

print('Welcome to Tic Tac Toe!')

while True:
# Reset the board
theBoard = [' '] * 10
playerLetter, computerLetter = inputPlayerLetter()
turn = whoGoesFirst()
print('The ' + turn + ' will go first.')
gameIsPlaying = True

while gameIsPlaying:
if turn == 'player':
# Player’s turn.
drawBoard(theBoard)
move = getPlayerMove(theBoard)
makeMove(theBoard, playerLetter, move)

if isWinner(theBoard, playerLetter):
drawBoard(theBoard)
print('Hooray! You have won the game!')
gameIsPlaying = False
else:
if isBoardFull(theBoard):
drawBoard(theBoard)
print('The game is a tie!')
break
else:
turn = 'computer'

else:
# Computer’s turn.
move = getComputerMove(theBoard, computerLetter)
makeMove(theBoard, computerLetter, move)

if isWinner(theBoard, computerLetter):
drawBoard(theBoard)
print('The computer has beaten you! You lose.')
gameIsPlaying = False
else:
if isBoardFull(theBoard):
drawBoard(theBoard)
print('The game is a tie!')
break
else:
turn = 'player'

if not playAgain():
break

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.