过年回家，都会约上亲朋好友聚聚会，会上经常会打麻将，斗地主，斗牛。在这些游戏中，斗牛是最受欢迎的，因为可以很多人一起玩，而且没有技术含量，都是看运气（专业术语是概率）。
斗牛的玩法是：
- 1、把牌中的JQK都拿出来
- 2、每个人发5张牌
- 3、如果5张牌中任意三张加在一起是10的 倍数，就是有牛。剩下两张牌的和的10的余数就是牛数。
牌的大小：
4条 > 3条 > 牛十 > 牛九 > …… > 牛一 >没有牛
而这些牌出现的概率是有多少呢？
由于只有四十张牌，所以采用了既简单，又有效率的方法枚举来计算。
计算的结果：
- 所有牌的组合数：658008
- 出现四条的组合数:360,概率 :0.05%
- 出现三条的组合数:25200,概率 :3.83%
- 出现牛十的组合数:42432,概率 :6.45%
- 出现牛九或牛八的组合数:87296,概率 :13.27%
- 出现牛一到牛七的组合数:306112,概率 :46.52%
- 出现没有牛的组合数:196608,概率 :29.88%
所以有七成的概率是有牛或以上的，所以如果你经常遇到没有牛，说明你的运气非常差或者本来是有牛的，但是你没有找出来。
Python源代码：
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# encoding=utf-8__author__ = 'kevinlu1010@qq.com'import osimport cPicklefrom copy import copyfrom collections import Counterimport itertools'''计算斗牛游戏的概率'''class Poker(): ''' 一张牌 ''' def __init__(self, num, type): self.num = num # 牌数 self.type = type # 花色class GamePoker(): ''' 一手牌，即5张Poker ''' COMMON_NIU = 1 # 普通的牛，即牛一-牛七 NO_NIU = 0 # 没有牛 EIGHT_NINE_NIU = 2 # 牛九或牛八 TEN_NIU = 3 # 牛十 THREE_SAME = 4 # 三条 FOUR_SAME = 5 # 四条 def __init__(self, pokers): assert len(pokers) == 5 self.pokers = pokers self.num_pokers = [p.num for p in self.pokers] # self.weight = None # 牌的权重，权重大的牌胜 # self.money_weight = None # 如果该牌赢，赢钱的权重 self.result = self.sumary() def is_niu(self): ''' 是否有牛 :return: ''' # if self.is_three_same(): # return 0 for three in itertools.combinations(self.num_pokers, 3): if sum(three) % 10 == 0: left = copy(self.num_pokers) for item in three: left.remove(item) point = sum(left) % 10 return 10 if point == 0 else point return 0 def is_three_same(self): ''' 是否3条 :return: ''' # if self.is_four_same(): # return 0 count = Counter([p.num for p in self.pokers]) for num in count: if count[num] == 3: return num return 0 def is_four_same(self): ''' 是否4条 :return: ''' count = Counter([p.num for p in self.pokers]) for num in count: if count[num] == 4: return num return 0 def sumary(self): ''' 计算牌 ''' if self.is_four_same(): return GamePoker.FOUR_SAME if self.is_three_same(): return GamePoker.THREE_SAME niu_point = self.is_niu() if niu_point in (8, 9): return GamePoker.EIGHT_NINE_NIU elif niu_point == 10: return GamePoker.TEN_NIU elif niu_point > 0: return GamePoker.COMMON_NIU else: return GamePoker.NO_NIUdef get_all_pokers(): ''' 生成所有的Poker，共四十个 :return: ''' pokers = [] for i in range(1, 11): for j in ('A', 'B', 'C', 'D'): pokers.append(Poker(i, j)) return pokersdef get_all_game_poker(is_new=0): ''' 生成所有game_poker :param pokers: :return: ''' pokers = get_all_pokers() game_pokers = [] if not is_new and os.path.exists('game_pokers'): with open('game_pokers', 'r') as f: return cPickle.loads(f.read()) for pokers in itertools.combinations(pokers, 5): # 5代表五张牌 game_pokers.append(GamePoker(pokers)) with open('game_pokers', 'w') as f: f.write(cPickle.dumps(game_pokers)) return game_pokersdef print_rate(game_pokers): total_num = float(len(game_pokers)) four_num = len([game_poker for game_poker in game_pokers if game_poker.result == GamePoker.FOUR_SAME]) three_num = len([game_poker for game_poker in game_pokers if game_poker.result == GamePoker.THREE_SAME]) ten_num = len([game_poker for game_poker in game_pokers if game_poker.result == GamePoker.TEN_NIU]) eight_nine_num = len([game_poker for game_poker in game_pokers if game_poker.result == GamePoker.EIGHT_NINE_NIU]) common_num = len([game_poker for game_poker in game_pokers if game_poker.result == GamePoker.COMMON_NIU]) no_num = len([game_poker for game_poker in game_pokers if game_poker.result == GamePoker.NO_NIU]) print '所有牌的组合数：%d' % total_num print '出现四条的组合数:%d,概率 :%.2f%%' % (four_num, four_num * 100 / total_num) print '出现三条的组合数:%d,概率 :%.2f%%' % (three_num, three_num * 100 / total_num) print '出现牛十的组合数:%d,概率 :%.2f%%' % (ten_num, ten_num * 100 / total_num) print '出现牛九或牛八的组合数:%d,概率 :%.2f%%' % (eight_nine_num, eight_nine_num * 100 / total_num) print '出现牛一到牛七的组合数:%d,概率 :%.2f%%' % (common_num, common_num * 100 / total_num) print '出现没有牛的组合数:%d,概率 :%.2f%%' % (no_num, no_num * 100 / total_num)def main(): game_pokers = get_all_game_poker() # 658008种 print_rate(game_pokers)main() |
以上就是Python计算斗牛游戏的概率相关内容，希望对大家的学习有所帮助。
