我已经写了一个基本的tic tac toe游戏，并试图为游戏的ai实现minimax算法。但是，运行脚本时，该算法似乎无法正常工作。 示例:( ai为O）
|X|X| |
-------
| | | |
-------
| |O| |
-------
结果
|X|X| |
-------
| | |O|
-------
| |O| |
-------
除此之外，该算法通常会覆盖玩家之前的动作
完整的脚本
import random
import time
import sys
from sys import maxsize
#converts numbers from the board to X O and "" for printing out the board
def numToSymbol(board):
visual = board
for i in range(0, 9):
if visual[i] == -1:
visual[i]= "X"
elif visual[i] == 1:
visual[i] = "O"
elif visual[i] == 0:
visual[i] = " "
return visual
def symbolToNum(visual):
board = visual
for i in range(0, 9):
if board[i] == "X":
board[i] = -1
elif board[i] == "O":
board[i] = 1
elif board[i] == " ":
board[i] = 0
return board
# prints the board, first coverting numbers throught numtoSymbol
def drawBoard():
visual = numToSymbol(board)
print(
"|"+ str(visual[0]) + "|" + str(visual[1]) + "|" + str(visual[2]) + "| \n"
"-------\n"
"|"+ str(visual[3]) + "|" + str(visual[4]) + "|" + str(visual[5]) + "| \n"
"-------\n"
"|"+ str(visual[6]) + "|" + str(visual[7]) + "|" + str(visual[8]) + "| \n"
"-------")
symbolToNum(visual)
# checks the possible options for 3 in a row and if any are all held by one side returns true
def checkWin(board, winConditions, ai):
if ai == True:
win = 3
if ai == False:
win = -3
for row in winConditions:
checkA = board[row[0]]
checkB = board[row[1]]
checkC = board[row[2]]
if checkA + checkB + checkC == int(win):
return True
return False
def checkDraw(board):
emptyTile = 9
for tile in board:
if tile != 0:
emptyTile -= 1
if emptyTile == 0:
completion(2)
def availableMoves(board, bonus):
availableSlots = []
for position in range(0,9):
if board[position] == 0:
availableSlots.append(position + bonus)
return availableSlots
def playerTurn(board, remainingTurns):
board = board
checkDraw(board)
visual =drawBoard()
print("pick one of the available slots \n")
availableSlots = availableMoves(board, 1)
print(availableSlots)
choice = int(input('Select a tile from those shown above:\n')) -1
while True:
if 0 <= choice <= 8:
if board[choice] == 0:
board[choice] = -1
break
else:
choice = int(input('Select a tile from those shown above which has not already been selected:\n')) -1
else:
choice = int(input('Select a tile from those shown above:\n')) -1
visual = drawBoard()
if checkWin(board, winConditions, False) == True:
completion(0)
else:
aiTurn(board, remainingTurns - 1)
class Node(object):
def __init__(self, remainingTurns, playerNum, board, value = 0):
self.depth = remainingTurns
self.playerNum = playerNum
self.board = board[::]
self.value = value
self.moves = availableMoves(self.board, 0)
self.children = []
self.createChildren()
def availableMoves(self, board):
self.availableSlots = []
for position in range(0,9):
if board[position] == 0:
availableSlots.append(position)
return self.availableSlots
def winCheck(self, state, playerNum):
self.winConditions = [[0, 1, 2],[3, 4, 5],[6, 7, 8],[0, 3, 6],[1, 4, 7],[2, 5, 8],[0, 4, 8],[2, 4, 6]]
self.win = 3
for row in self.winConditions:
self.checkA = self.state[row[0]]
self.checkB = self.state[row[1]]
self.checkC = self.state[row[2]]
if self.checkA + self.checkB + self.checkC == int(self.win * self.playerNum):
return True
return False
def createChildren(self):
if self.depth > 0:
for i in self.moves:
self.state = self.board
self.state[i] = self.playerNum
print(board)
self.children.append(Node(self.depth - 1, self.playerNum * -1, self.state, self.realVal(self.state, self.playerNum) ))
def realVal(self, value, playerNum):
value = self.winCheck(self.state, self.playerNum)
if value == True:
return maxsize * self.playerNum
else:
return 0
def minimax(node, depth, playerNum):
if depth == 0 or abs(node.value) == maxsize:
return node.value
bestValue = maxsize * -playerNum
for i in range(len(node.children)):
child = node.children[i]
val = minimax(child, depth - 1, -playerNum)
if (abs(maxsize * playerNum - val) < abs(maxsize * playerNum - bestValue)):
bestValue = val
return bestValue
def aiTurn(board, remainingTurns):
checkDraw(board)
print('Waiting for ai')
time.sleep(2)
board = board
state = board
currentPlayer = 1
tree = Node(remainingTurns, currentPlayer, state)
bestChoice = -100
bestValue = maxsize * -1
for i in range(len(tree.children)):
n_child = tree.children[i]
i_val = minimax(n_child, remainingTurns, -currentPlayer,)
if (abs(currentPlayer * maxsize - i_val) <= abs(currentPlayer * maxsize - bestValue)):
bestValue = i_val
bestChoice = i
print(bestChoice)
board[bestChoice] = 1
if checkWin(board, winConditions, True) == True:
completion(1)
else:
playerTurn(board, remainingTurns - 1)
def completion(state):
if state == 1:
print('The computer has won this game.')
choice = str(input('press y if you would like to play another game; Press n if you would not \n'))
if choice == 'y' or choice == 'Y':
playGame()
else:
sys.exit()
if state == 0:
print('you win!')
choice = str(input('press y if you would like to play another game; Press n if you would not \n'))
if choice == 'y' or choice == 'Y':
playGame()
else:
sys.exit()
if state == 2:
print('you drew')
choice = str(input('press y if you would like to play another game; Press n if you would not \n'))
if choice == 'y' or choice == 'Y':
playGame()
else:
sys.exit()
def playGame():
global board
board = [0,0,0,0,0,0,0,0,0]
global winConditions
winConditions = [
[0, 1, 2],
[3, 4, 5],
[6, 7, 8],
[0, 3, 6],
[1, 4, 7],
[2, 5, 8],
[0, 4, 8],
[2, 4, 6]
]
global remainingTurns
remainingTurns = 9
playerFirst = random.choice([True, False])
if playerFirst == True:
playerTurn(board, remainingTurns)
else:
aiTurn(board, remainingTurns)
if __name__ == '__main__':
playGame()