[Python] 黑白棋（翻转棋）小游戏

时间 2020-05-23

原文原文链接

[Python] 黑白棋（翻转棋）小游戏

游戏介绍

黑白棋(Reversi or Othello)在西方和日本很流行。游戏经过相互翻转对方的棋子，最后以棋盘上谁的棋子多来判断胜负。python

规则

黑白棋的每颗棋子由黑白两色组成，一面白，一面黑。每次落子，把本方颜色的棋子放在棋盘的空格上，若在横、竖、斜八个方向的任一方向上有本方棋子，则被夹在中间的对手棋子所有翻转为本方棋子颜色;而且仅在能够翻转棋子的地方才能落子。若是一方至少有一步合法棋步可下，他就必须落子，不得弃权。git

棋盘已满或双方都没有棋子可下时棋局结束，以棋子数目来计算胜负，棋子多的一方获胜。在棋盘尚未下满时，若是一方的棋子已经被对方吃光，则棋局也结束，将对手棋子吃光的一方获胜。github

胜负断定

两位玩家轮流下棋，直到一方没有符合规则的落子位置，在这种状况下，剩下的一方继续下棋，直到对手有了能够落子的位置。此时，恢复二者轮流下棋的顺序。若是一方落子在非法位置，则视为放弃本次对弈，对方获胜。ui

游戏结束的条件:spa

整个棋盘满了
一方的棋子已经被对方吃光
两名玩家都没有能够落子的棋盘格
一方落子在非法位置

前3种状况以棋子数目来计算胜负，棋子多的一方获胜;第四种状况断定对方获胜。code

人机对弈流程

首先，程序询问用户棋盘的大小。接着，程序询问用户“计算机持黑棋仍是白棋”。orm

在本程序中，咱们用字母’X’表明黑棋，用字母’O’表明白棋，而且假设老是黑棋玩家先走。blog

因此，若是计算机持黑棋，计算机就先走; 不然，程序提示人类玩家先走。游戏

每走一步，程序输出棋盘。黑白棋玩家轮流下棋，直到一个玩家无符合规则的落子位置。ip

此时，程序输出信息“O player has no valid move.”(假设白棋玩家无棋可走)，而且提示黑棋玩家继续下棋。

每走一步，程序除输出棋盘外，还要检测游戏是否结束。若是程序检查出游戏结束，输出输赢信息并停止程序。输赢信息能够是: “O player wins.”, “X player wins.” 或者“Draw!”. 若是用户落子非法，程序应检测到而且输出“Invalid move.”，结束程序，宣布赢家。

计算机选择落子位置的策略

对每一个可能的落子位置，都进行尝试，计算该位置的“分值”(能够翻转的对手棋子数量)，分值越高则在该位置落子越有利。计算每一个可能位置的分值，选择最大值位置落子。须要注意的是:可能有2个或多个棋盘格有相同的分值。这种状况下，选择行字母最小的棋盘格。若是两个棋盘格分值相同且在同一行，则选择列字母较小的棋盘格。

程序执行

代码

完整代码见
代码仓库

棋盘代码

#!/usr/bin/python 
# -*- coding: utf-8 -*-

class Board():
    def __init__(self, n):
        self.n = n
        self.board = self.generateBoard()
        self.chess = {0: '.', 1: 'O', 2: 'X'}

    def generateBoard(self):
        # 0 empty 1 white 2 black
        i = int(self.n / 2)
        board = [[0] * self.n for _ in range(self.n)]
        board[i][i]=board[i-1][i-1] = 1
        board[i][i-1]=board[i-1][i] = 2
        return board

    def draw(self):
        index = 'abcdefghijklmnopqrstuvwxyz'
        print(' ',*index[:self.n])
        for h,row in zip(index,self.board):
            print(h,*map('.OX'.__getitem__,row))
        print()

游戏逻辑

#!/usr/bin/python 
# -*- coding: utf-8 -*-

from board import Board
import itertools
import operator
import collections
from functools import reduce
from constant import Status

class Reversi():

    _DIRECTIONS = [(1,0),(1,1),(1,-1),(-1,0),(-1,1),(-1,-1),(0,1),(0,-1)]

    def __init__(self, n, turn):
        self.n = n                                              # board dimension
        self.b = Board(n)                                       # board
        self.turn = 0 if turn == 'X' or turn == 'x' else 1      # player turn
        self.step = 1                                           # game step
        self.status = Status.WAIT                               # game status

    def isValidPosition(self,x,y):
        return 0 <= x < self.n and 0 <= y < self.n
    
    def nextPosition(self,direction,x,y):
        x+=direction[0]
        y+=direction[1]
        return x,y
    
    def score(self,r,c):
        return list(itertools.chain.from_iterable([self.scoreDirection(r+m[0],c+m[1],m,self.step%2+1,[]) for m in Reversi._DIRECTIONS]))

    def scoreDirection(self,x,y,direction,color,turn):
        if not self.isValidPosition(x,y) or self.b.board[x][y]==0 :
            return []
        if self.b.board[x][y]!=color:
            turn+=[(x,y)]
            return self.scoreDirection(*self.nextPosition(direction,x,y),direction,color,turn)
        else:
            return turn

    def checkPut(self, pos):
        # check person put
        assert len(pos)>=2 , 'move position disable'
        r = ord(pos[0]) - 97
        c = ord(pos[1]) - 97
        assert 0 <= r < self.n and 0 <= c < self.n, 'move position disable'
        turnList = self.score(r, c)
        if turnList:
            # turn chess
            for x,y in turnList+[(r,c)]:
                self.b.board[x][y] = self.step % 2+1
            return True
        else:
            return False

    def checkGame(self):
        # check game status
        empty,oNum,xNum = operator.itemgetter(0,1,2)(collections.Counter(itertools.chain.from_iterable(self.b.board)))
        hasPut = True
        pos,turnList = self.aiPut()
        if not turnList:
            self.step += 1
            posNext,turnListNext = self.aiPut()
            if not turnListNext:
                hasPut = False
            else:
                self.step -= 1
                print('{} player has no valid move'.format(self.b.chess[self.step % 2+1]))
                self.step -= 1
                self.turn -= 1
                print('{} player go on'.format(self.b.chess[self.step % 2+1]))
        if empty ==0 or oNum==0 or xNum == 0 or not hasPut:
            self.status = [Status.DRAW.value,Status.OWIN.value,Status.XWIN.value][(oNum > xNum)-(oNum<xNum)]
    
    def cmp(self,a,b):
        if len(a[1])>len(b[1]):
            return a 
        elif len(a[1])==len(b[1]) and a[0]<b[0]:
            return a
        else:
            return b
            
    def aiPut(self):
        # computer put
        allPos = filter(lambda pos : self.b.board[pos[0]][pos[1]]==0,itertools.product(range(self.n),repeat=2))
        allScoreForPos  = map(lambda pos: [pos,self.score(pos[0],pos[1])],allPos)
        maxScorePos = reduce(self.cmp,allScoreForPos,[(),[]])
        return maxScorePos[0],maxScorePos[1]

    def aiPlay(self):
        pos,turnList = self.aiPut()
        if turnList:
            print('Computer places {} at {}'.format(self.b.chess[self.step % 2+1],chr(pos[0]+97)+chr(pos[1]+97)))
            for x,y in turnList+[pos]:
                self.b.board[x][y] = self.step % 2+1
            reversi.b.draw()
            self.step += 1
            self.turn += 1

    def pPlay(self):
        pos = input('Enter move for {} (RowCol):'.format(self.b.chess[self.step % 2+1]))
        if self.checkPut(pos):
            reversi.b.draw()
            self.step += 1
            self.turn += 1
        else:
            print('Invalid move')

    def play(self):
        self.status = Status.ONGOING
        plays = [self.aiPlay,self.pPlay]
        while self.status == Status.ONGOING:
            plays[self.turn % len(plays)]()
            self.checkGame()
        else:
            print('Game over. {}'.format(Status(self.status)))

if __name__ == "__main__":
    print('Enter the board dimension:')
    try:
        n = int(input())
    except Exception as e:
        print('the board dimension is invalid, start game with default dimension = 4')
        n = 4
    assert 4 <= n <= 26 and n % 2 == 0, 'the board dimension is disable'
    print('Computer plays (X/O):')
    turn = input()
    assert turn in ['X','x','O', 'o'], 'the symbol of computer is disable'
    # generate game
    reversi = Reversi(n, turn)
    # draw board
    reversi.b.draw()
    reversi.play()
    input('Enter to quit')