#全局常量
best_weizhi= (4, 0, 2, 6, 8, 1, 3, 5, 7)
win = ((0, 1, 2), ?(3, 4, 5), (6, 7, 8), ?(0, 3, 6),(1, 4, 7), ?(2, 5, 8), (0, 4, 8), ?(2, 4, 6))?
X = "X"
O = "O"
EMPTY = " "
#定義函數(shù)產(chǎn)生一個新的棋盤
def new_board():
? ? board = []
? ? for square in range(9):
? ? ? ? board.append(EMPTY)
? ? return board
#詢問該誰下棋
def ask_yes_no(question):
? ? response = None
? ? #如果輸入不是"y", "n"，繼續(xù)重新輸入
? ? while response not in ("y", "n"):?? ?
? ? ? ? ? ?response = input(question).lower()
? ? return response
#詢問誰先走，先走方為X，后走方為O
#函數(shù)返回電腦方、玩家的角色代號
def pieces():
? ? go_first = ask_yes_no("玩家你是否先走 (y/n): ")
? ? if go_first == "y":
? ? ? ? print("\n玩家你先走.")
? ? ? ? human = X
? ? ? ? computer = O
? ? else:
? ? ? ? print("\n電腦先走.")
? ? ? ? computer = X
? ? ? ? human = O
? ? return computer, human
#顯示棋盤
def display_board(board):
? ? board2=board[:] ? ? #創(chuàng)建副本，修改不影響原來列表board
? ? for i in range(len(board)):
? ? ? ? if board[i]==EMPTY:
? ? ? ? ? ? board2[i]=i
? ? print("\t", board2[0], "|", board2[1], "|", board2[2])
? ? print("\t", "---------")
? ? print("\t", board2[3], "|", board2[4], "|", board2[5])
? ? print("\t", "---------")
? ? print("\t", board2[6], "|", board2[7], "|", board2[8], "\n")
#輸入你想下的位置數(shù)字
def ask_number(question, low, high):
? ? response = None
? ? while response not in range(low, high):
? ? ? ? response = int(input(question))
? ? return response
#產(chǎn)生可以合法走棋位置序列（也就是還未下過子位置）
def legal_moves(board):
? ? moves = []
? ? for i in range(9):
? ? ? ? if board[i] == EMPTY:
? ? ? ? ? ? moves.append(i)
? ? return moves
#判斷輸贏
def winner(board):
? ? for row in win:
? ? ? ? if board[row[0]] == board[row[1]] == board[row[2]] != EMPTY:
? ? ? ? ? ? winner = board[row[0]]
? ? ? ? ? ? return winner ? ? ? #返回贏方
? ? #棋盤沒有空位置
? ? if EMPTY not in board:
? ? ? ? return "True"?? ??? ??? ?#"平局和棋，游戲結(jié)束"
? ? return False
#人走棋
def human_move(board, human):
? ? legal = legal_moves(board)
? ? move = None
? ? while move not in legal:
? ? ? ? move = ask_number("你走那個位置? (0 - 9):", 0, 9)
? ? ? ? if move not in legal:
? ? ? ? ? ? print("\n此位置已經(jīng)落過子了")
? ? return move
#電腦走棋
def computer_move(board, computer, human):
? ? # make a copy to work with since function will be changing list
? ? board = board[:] ? ? #創(chuàng)建副本，修改不影響原來列表board
? ? #按優(yōu)劣順序排序的下棋位置best_weizhi
? ? # 如果電腦能贏，就走那個位置
? ? for move in legal_moves(board):
? ? ? ? board[move] = computer
? ? ? ? if winner(board) == computer:
? ? ? ? ? ? print("電腦下棋位置是" ,move)
? ? ? ? ? ? return move
? ? ? ? # 取消走棋方案
? ? ? ? board[move] = EMPTY
? ? # 如果玩家能贏，就堵住那個位置
? ? for move in legal_moves(board):
? ? ? ? board[move] = human
? ? ? ? if winner(board) == human:
? ? ? ? ? ? print("電腦下棋位置是" ,move)
? ? ? ? ? ? return move
? ? ? ? #取消走棋方案
? ? ? ? board[move] = EMPTY
? ? #不是上面情況則，也就是這一輪時都贏不了則
? ? #從最佳下棋位置表中挑出第一個合法位置
? ? for move in best_weizhi:
? ? ? ? if move in legal_moves(board):
? ? ? ? ? ? print("電腦下棋位置是" ,move)
? ? ? ? ? ? return move
#轉(zhuǎn)換角色
def next_turn(turn):
? ? if turn == X:
? ? ? ? return O
? ? else:
? ? ? ? return X
#主方法：
def main():
? ? computer, human = pieces()
? ? turn = X
? ? board = new_board()
? ? display_board(board)
? ??
? ? while not winner(board):
? ? ? ? if turn == human:
? ? ? ? ? ? move = human_move(board, human)
? ? ? ? ? ? board[move] = human
? ? ? ? else:
? ? ? ? ? ? move = computer_move(board, computer, human)
? ? ? ? ? ? board[move] = computer
? ? ? ? display_board(board)
? ? ? ? turn = next_turn(turn)
? ? ? ? the_winner = winner(board)
? ? #游戲結(jié)束輸出輸贏信息
? ? if the_winner == computer:
? ? ? ? print("電腦贏!\n") ? ?
? ? elif the_winner == human: ? ? ? ??
? ? ? ? print("玩家贏!\n")
? ? elif the_winner == "True":?? ?#"平局" ? ? ? ?
? ? ? ? print("平局,和棋，游戲結(jié)束\n")

# start the program
main()
input("按任意鍵退出游戲.")