python井字棋最大最小算法_python井字棋算法及代码
井字棋盘看起来像一个大的井字符号(#)，有9 个空格，可以包含X、O 或
关于落子问题
由于只能采用键盘输入，所以需要对棋盘进行坐标表示；
即直接用1-9个9个数字来表示位置，
7|8|9
-+-+-
4|5|6
-+-+-
1|2|3
其索引顺序与数字键盘上的数字键排列一致，下棋时看着数字键下，较为简便。
计算机的算法--寻找最佳落子位置
首先简单的将棋盘划分为三个部分——中心(1)，角(4)，边(4)。
中心虽然只有一个但却不是最重要的，三个部分落子的优先顺序依次为：角、中心、边。
因此，井字棋的计算机算法计算最佳落子位置的顺序如下：
1 直接落子获胜
2 阻止玩家获胜
3 在角上落子
4 在中心落子
5 在边上落子
游戏流程
1、开始
2、选子 X或者O
3、随机先手
4、轮流下棋
5、是否分出胜负
5.1 分出胜负 跳到6
5.2 未分出胜负 跳到4
6、再来一局
6.1是， 跳到2
6.2否， 退出
游戏代码：
import random
def printBoard(borad):
print(borad[7] + '|' + borad[8] + '|' + borad[9])
print('-+-+-')
print(borad[4] + '|' + borad[5] + '|' + borad[6])
print('-+-+-')
print(borad[1] + '|' + borad[2] + '|' + borad[3])
'''printBoard 定义了棋盘打印输出函数
与数字键盘排列一致'''
def inputPlayerLetter():
'''#让玩家选择棋子
返回一个列表，显示玩家和电脑的棋子类型
'''
letter = ''
while not (letter == 'X' or letter == 'O'):
print('Do you want to be X or O?')
letter = input().upper()
if letter == 'X':
return ['X', 'O']
else:
return ['O', 'X']
def whoGoesFirst():
'''随机先手'''
if random.randint(0, 1) == 0:
return 'Computer'
else:
return 'Player'
def playAgain():
'''再玩一次？'''
print('Do you want to play again?(yes or no)')
return input().lower().startswith('y')
def makeMove(board, letter, move):
'''落子'''
board[move] = letter
def isWinner(board, occupy):
判断是否获胜
return ((board[1] == occupy and board[2] == occupy and board[3] == occupy) or
(board[4] == occupy and board[5] == occupy and board[6] == occupy) or
(board[7] == occupy and board[8] == occupy and board[9] == occupy) or
(board[1] == occupy and board[4] == occupy and board[7] == occupy) or
(board[2] == occupy and board[5] == occupy and board[8] == occupy) or
(board[3] == occupy and board[6] == occupy and board[9] == occupy) or
(board[1] == occupy and board[5] == occupy and board[9] == occupy) or
(board[3] == occupy and board[5] == occupy and board[7] == occupy))
def getBoardCopy(board):
复制一份棋盘给电脑落子使用
depuBoard = []
for i in board:
depuBoard.append(i)
return depuBoard
def isSpaceFree(board, move):
判断这个位置是否有子，无子返回True
return board[move] == ' '
def getPlayerMove(board):
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 choosePossibleMoverFromList(board, moveList):
随机返回一个可以落子的坐标，若无子可下，则返回None
possibleMoves = []
for i in moveList:
if isSpaceFree(board, i):
possibleMoves.append(i)
if len(possibleMoves) != 0:
return random.choice(possibleMoves)
else:
return None
def getComputerMove(board, computerLetter):
确定电脑的落子位置
if computerLetter == 'X':
playerLetter == 'O'
else:
playerLetter == 'X'
'''先判断电脑方能否通过一次落子直接获得游戏胜利'''
for i in range(1, 10):
copy = getBoardCopy(board)
if isSpaceFree(copy, i):
makeMove(copy, computerLetter, i)
if isWinner(copy, computerLetter):
return i
'''判断玩家下一次落子是否获胜，若能，则再该点落子'''
for i in range(1, 10):
copy = getBoardCopy(board)
if isSpaceFree(copy, i):
makeMove(copy, playerLetter, i)
if isWinner(copy, playerLetter):
return i
'''若角上能落子，则在角上落子'''
move = choosePossibleMoverFromList(board, [1, 3, 5, 7])
if move != None:
return move
'''若中心能落子，则在中心落子'''
if isSpaceFree(board, 5):
return 5
'''若边上能落子，则在边上落子'''
return choosePossibleMoverFromList(board, [2, 4, 6, 8])
def isBoardFull(board):
''' 如果棋盘满了，返回True'''
for i in range(1, 10):
if isSpaceFree(board, i):
return False
return True
print('Welcome to the TicTacToe game!')
while True:
update board
theBoard = [' '] * 10
playerLetter, computerLetter = inputPlayerLetter()
turn = whoGoesFirst()
print('The ' + turn + ' will go first.')
gameIsPlaying = True
while gameIsPlaying:
if turn == 'Player':
# 玩家回合
printBoard(theBoard)
move = getPlayerMove(theBoard)
makeMove(theBoard, playerLetter, move)
if isWinner(theBoard, playerLetter):
printBoard(theBoard)
print('Wow!!!You win the game!!!')
gameIsPlaying = False
else:
if isBoardFull(theBoard):
printBoard(theBoard)
print('The game is tie')
break
else:
turn = 'Computer'
else:
# 电脑回合
move = getComputerMove(theBoard, computerLetter)
makeMove(theBoard, computerLetter, move)
if isWinner(theBoard, computerLetter):
printBoard(theBoard)
print('Oh!,The computer win!,You lose.')
gameIsPlaying = False
else:
if isBoardFull(theBoard):
printBoard(theBoard)
print('The game is tie')
break
else:
turn = 'Player'
if not playAgain():
break