python 五子棋AI實現（2）：棋型評估函數實現
五子棋基本棋型介紹
參考資料：http://game.onegreen.net/wzq/HTML/142336.html
最常見的基本棋型大體有以下幾種：連五，活四，衝四，活三，眠三，活二，眠二。
① 連五：顧名思義，五顆同色棋子連在一起，不需要多講。
圖2-1
② 活四：有兩個連五點（即有兩個點可以形成五），圖中白點即爲連五點。
稍微思考一下就能發現活四出現的時候，如果對方單純過來防守的話，是已經無法阻止自己連五了。
圖2-2
③ 衝四：有一個連五點，如下面三圖，均爲衝四棋型。圖中白點爲連五點。
相對比活四來說，衝四的威脅性就小了很多，因爲這個時候，對方只要跟着防守在那個唯一的連五點上，衝四就沒法形成連五。
圖2-3
圖2-4
圖2-5
④ 活三：可以形成活四的三，如下圖，代表兩種最基本的活三棋型。圖中白點爲活四點。
活三棋型是我們進攻中最常見的一種，因爲活三之後，如果對方不以理會，將可以下一手將活三變成活四，而我們知道活四是已經無法單純防守住了。所以，當我們面對活三的時候，需要非常謹慎對待。在自己沒有更好的進攻手段的情況下，需要對其進行防守，以防止其形成可怕的活四棋型。
圖2-6 
圖2-7 
其中圖2-7中間跳着一格的活三，也可以叫做跳活三。
⑤ 眠三：只能夠形成衝四的三，如下各圖，分別代表最基礎的六種眠三形狀。圖中白點代表衝四點。眠三的棋型與活三的棋型相比，危險係數下降不少，因爲眠三棋型即使不去防守，下一手它也只能形成衝四，而對於單純的衝四棋型，我們知道，是可以防守住的。
圖2-8 
圖2-9 
圖2-10 
圖2-11
圖2-12 
圖2-13 
如上所示，眠三的形狀是很豐富的。對於初學者，在下棋過程中，很容易忽略不常見的眠三形狀，例如圖2-13所示的眠三。
有新手學了活三眠三後，會提出疑問，說活三也可以形成衝四啊，那豈不是也可以叫眠三？
會提出這個問題，說明對眠三定義看得不夠仔細：眠三的的定義是，只能夠形成衝四的三。而活三可以形成眠三，但也能夠形成活四。
此外，在五子棋中，活四棋型比衝四棋型具有更大的優勢，所以，我們在既能夠形成活四又能夠形成衝四時，會選擇形成活四。
溫馨提示：學會判斷一個三到底是活三還是眠三是非常重要的。所以，需要好好體會。
後邊禁手判斷的時候也會有所應用。
⑥ 活二：能夠形成活三的二，如下圖，是三種基本的活二棋型。圖中白點爲活三點。
活二棋型看起來似乎很無害，因爲他下一手棋才能形成活三，等形成活三，我們再防守也不遲。但其實活二棋型是非常重要的，尤其是在開局階段，我們形成較多的活二棋型的話，當我們將活二變成活三時，才能夠令自己的活三綿綿不絕微風裏，讓對手防不勝防。
圖2-14 
圖2-15 
圖2-16 
⑦眠二：能夠形成眠三的二。圖中四個爲最基本的眠二棋型，細心且喜歡思考的同學會根據眠三介紹中的圖2-13找到與下列四個基本眠二棋型都不一樣的眠二。圖中白點爲眠三點。
圖2-17 
圖2-18 
圖2-19 
圖2-20 
評估方法介紹
由上面的介紹可知，有7種有效的棋型（連五，活四，衝四，活三，眠三，活二，眠二），我們可以創建黑棋和白棋兩個數組，記錄棋盤上黑棋和白棋分別形成的所有棋型的個數，然後按照一定的規則進行評分。
如何記錄棋盤上的棋形個數，一個很直觀的方法是，棋盤上有15條水平線，15條豎直線，不考慮長度小於5的斜線，有21條從左上到右下的斜線，21條從左下到右上的斜線。然後對每一條線分別對黑棋和白棋查找是否有符合的棋型。這種方法比較直觀，但是實現起來不方便。有興趣的可以嘗試下。
這裏用的方法是，對整個棋盤進行遍歷，對於每一個白棋或黑棋，以它爲中心，記錄符合的棋型個數。
具體實現方式如下：
-
遍歷棋盤上的每個點，如果是黑棋或白旗，則對這個點所在四個方向形成的四條線分別進行評估。四個方向即水平，豎直，兩個斜線( \ , / ），四個方向依次按照從左到右， 從上到下，從左上到右下，從左下到右上 來檢測。
-
對於具體的一條線，如下圖，已選取點爲中心，取該方向上前面四個點，後面四個點，組成一個長度爲9的數組。
![線1]()
然後找下和中心點相連的同色棋子有幾個，比如下圖，相連的白色棋子有3個，根據相連棋子的個數再分別進行判斷，最後得出這行屬於上面說的哪一種棋型。具體判斷可以看代碼中的 analysisLine 函數.
這裏有個注意點，在評估白旗1的時候，白棋3和5已經被判斷過，所以要標記下，下次遍歷到這個方向的白棋3和5，需要跳過，避免重複統計棋型。
![線2]()
-
根據棋盤上黑棋和白棋的棋型統計信息，按照一定規則進行評分。
假設形成該棋局的最後一步是黑棋下的，則最後的評分是（黑棋得分 - 白棋得分），在相同棋型相同個數的情況下，白棋會佔優，因爲下一步是白棋下。比如黑棋有個衝四，白棋有個衝四，顯然白棋佔優，因爲下一步白棋就能成連五。
按照下面的規則依次匹配，下面設的評分值是可以優化調整的：
前面9條爲必殺情況，會直接返回評分，- 黑棋連5，評分爲10000
- 白棋連5，評分爲 -10000
- 黑棋兩個衝四可以當成一個活四
- 白棋有活四，評分爲 -9050
- 白棋有衝四，評分爲 -9040
- 黑棋有活四，評分爲 9030
- 黑棋有衝四和活三，評分爲 9020
- 黑棋沒有衝四，且白棋有活三，評分爲 9010
- 黑棋有2個活三，且白棋沒有活三或眠三，評分爲 9000
- 下面針對黑棋或白棋的活三，眠三，活二，眠二的個數依次增加分數，評分爲（黑棋得分 - 白棋得分）
簡單AI介紹
有了評估函數，輪到AI下棋時，就要針對當前的棋局，找到一個最有利的位置來下。AI會嘗試在每個空點下棋，形成一個新的棋局，然後用評估函數來獲取這個棋局時的評分。從中選取評分最高的位置來就行了。
AI 獲取最有利位置的邏輯：
- 遍歷棋盤上的每一個空點：
在這個空點下棋，獲取新的棋局的評分
如果是更高的評分，則保存該位置
將這個位置恢復爲空點 - 獲得最高評分的位置
上面這段邏輯我們在後續的文章中會不斷優化，使得AI越來越厲害。
代碼實現
AI的實現都在ChessAI類中，record數組記錄所有位置的四個方向是否被檢測過。count二維數組記錄黑棋和白棋的棋型個數統計。pos_score 給棋盤上每個位置設一個初始分數，越靠近棋盤中心，分數越高，用來在最開始沒有任何棋型時的，AI優先選取靠中心的位置。
reset函數每次調用評估函數前都需要清一下之前的統計數據。
class ChessAI():
def __init__(self, chess_len):
self.len = chess_len
# [horizon, vertical, left diagonal, right diagonal]
self.record = [[[0,0,0,0] for x in range(chess_len)] for y in range(chess_len)]
self.count = [[0 for x in range(CHESS_TYPE_NUM)] for i in range(2)]
self.pos_score = [[(7 - max(abs(x - 7), abs(y - 7))) for x in range(chess_len)] for y in range(chess_len)]
def reset(self):
for y in range(self.len):
for x in range(self.len):
for i in range(4):
self.record[y][x][i] = 0
for i in range(len(self.count)):
for j in range(len(self.count[0])):
self.count[i][j] = 0
self.save_count = 0
findBestChess 函數就是AI的入口函數。
search 函數是上面AI邏輯的代碼實現，先通過 genmove 函數獲取棋盤上所有的空點，然後依次嘗試，獲得評分最高的位置並返回。
# get all positions that is empty
def genmove(self, board, turn):
moves = []
for y in range(self.len):
for x in range(self.len):
if board[y][x] == 0:
score = self.pos_score[y][x]
moves.append((score, x, y))
moves.sort(reverse=True)
return moves
def search(self, board, turn):
moves = self.genmove(board, turn)
bestmove = None
max_score = -0x7fffffff
for score, x, y in moves:
board[y][x] = turn.value
score = self.evaluate(board, turn)
board[y][x] = 0
if score > max_score:
max_score = score
bestmove = (max_score, x, y)
return bestmove
def findBestChess(self, board, turn):
time1 = time.time()
score, x, y = self.search(board, turn)
time2 = time.time()
print('time[%f] (%d, %d), score[%d] save[%d]' % ((time2-time1), x, y, score, self.save_count))
return (x, y)
evaluate函數, 就是上面評估方法的代碼實現，參數turn表示最近一手棋是誰下的，根據turn決定的mine（表示自己棋的值）和oppoent（表示對手棋的值，下一步棋由對手下），在對棋型評分時會用到。checkWin 是遊戲用來判斷是否有一方獲勝了。
其中調用的getScore函數就是對黑棋和白棋進行評分。
evaluatePoint函數就是對於一個位置的四個方向分別進行檢查。
def evaluate(self, board, turn, checkWin=False):
self.reset()
if turn == MAP_ENTRY_TYPE.MAP_PLAYER_ONE:
mine = 1
opponent = 2
else:
mine = 2
opponent = 1
for y in range(self.len):
for x in range(self.len):
if board[y][x] == mine:
self.evaluatePoint(board, x, y, mine, opponent)
elif board[y][x] == opponent:
self.evaluatePoint(board, x, y, opponent, mine)
mine_count = self.count[mine-1]
opponent_count = self.count[opponent-1]
if checkWin:
return mine_count[FIVE] > 0
else:
mscore, oscore = self.getScore(mine_count, opponent_count)
return (mscore - oscore)
def evaluatePoint(self, board, x, y, mine, opponent):
dir_offset = [(1, 0), (0, 1), (1, 1), (1, -1)] # direction from left to right
for i in range(4):
if self.record[y][x][i] == 0:
self.analysisLine(board, x, y, i, dir_offset[i], mine, opponent, self.count[mine-1])
else:
self.save_count += 1
analysisLine函數是判斷一條線上自己棋能形成棋型的代碼， mine表示自己棋的值，opponent表示對手棋的值。
要根據中心點相鄰己方棋子能連成的個數來分別判斷，己方棋值設爲M，對方棋值設爲P，空點值設爲X。具體可以看代碼中的註釋。
- 連成5個點，可以直接返回
- 連成4個點，要考慮是否被對手棋檔着，比如 PMMMMX
- 連成3個點，要考慮隔一個空點的情況，比如 MXMMMX。
- 連成2個點，要考慮隔一個空點的如情況，比如 MXMMX，MMXMM。
- 只有1個點，要考慮隔一個或二個空點的情況，比如 XMXMX，XMXXMX。
getLine函數，根據棋子的位置和方向，獲取上面說的長度爲9的線。有個取巧的地方，如果線上的位置超出了棋盤範圍，就將這個位置的值設爲對手的值，因爲超出範圍和被對手棋擋着，對棋型判斷的結果是一樣的。
setRecord函數 標記已經檢測過，需要跳過的棋子。
# line is fixed len 9: XXXXMXXXX
def getLine(self, board, x, y, dir_offset, mine, opponent):
line = [0 for i in range(9)]
tmp_x = x + (-5 * dir_offset[0])
tmp_y = y + (-5 * dir_offset[1])
for i in range(9):
tmp_x += dir_offset[0]
tmp_y += dir_offset[1]
if (tmp_x < 0 or tmp_x >= self.len or
tmp_y < 0 or tmp_y >= self.len):
line[i] = opponent # set out of range as opponent chess
else:
line[i] = board[tmp_y][tmp_x]
return line
def analysisLine(self, board, x, y, dir_index, dir_offset, mine, opponent, count):
# record line range[left, right] as analysized
def setRecord(self, x, y, left, right, dir_index, dir_offset):
tmp_x = x + (-5 + left) * dir_offset[0]
tmp_y = y + (-5 + left) * dir_offset[1]
for i in range(left, right+1):
tmp_x += dir_offset[0]
tmp_y += dir_offset[1]
self.record[tmp_y][tmp_x][dir_index] = 1
empty = MAP_ENTRY_TYPE.MAP_EMPTY.value
left_idx, right_idx = 4, 4
line = self.getLine(board, x, y, dir_offset, mine, opponent)
while right_idx < 8:
if line[right_idx+1] != mine:
break
right_idx += 1
while left_idx > 0:
if line[left_idx-1] != mine:
break
left_idx -= 1
left_range, right_range = left_idx, right_idx
while right_range < 8:
if line[right_range+1] == opponent:
break
right_range += 1
while left_range > 0:
if line[left_range-1] == opponent:
break
left_range -= 1
chess_range = right_range - left_range + 1
if chess_range < 5:
setRecord(self, x, y, left_range, right_range, dir_index, dir)
return CHESS_TYPE.NONE
setRecord(self, x, y, left_idx, right_idx, dir_index, dir)
m_range = right_idx - left_idx + 1
# M:mine chess, P:opponent chess or out of range, X: empty
if m_range == 5:
count[FIVE] += 1
# Live Four : XMMMMX
# Chong Four : XMMMMP, PMMMMX
if m_range == 4:
left_empty = right_empty = False
if line[left_idx-1] == empty:
left_empty = True
if line[right_idx+1] == empty:
right_empty = True
if left_empty and right_empty:
count[FOUR] += 1
elif left_empty or right_empty:
count[SFOUR] += 1
# Chong Four : MXMMM, MMMXM, the two types can both exist
# Live Three : XMMMXX, XXMMMX
# Sleep Three : PMMMX, XMMMP, PXMMMXP
if m_range == 3:
left_empty = right_empty = False
left_four = right_four = False
if line[left_idx-1] == empty:
if line[left_idx-2] == mine: # MXMMM
setRecord(self, x, y, left_idx-2, left_idx-1, dir_index, dir)
count[SFOUR] += 1
left_four = True
left_empty = True
if line[right_idx+1] == empty:
if line[right_idx+2] == mine: # MMMXM
setRecord(self, x, y, right_idx+1, right_idx+2, dir_index, dir)
count[SFOUR] += 1
right_four = True
right_empty = True
if left_four or right_four:
pass
elif left_empty and right_empty:
if chess_range > 5: # XMMMXX, XXMMMX
count[THREE] += 1
else: # PXMMMXP
count[STHREE] += 1
elif left_empty or right_empty: # PMMMX, XMMMP
count[STHREE] += 1
# Chong Four: MMXMM, only check right direction
# Live Three: XMXMMX, XMMXMX the two types can both exist
# Sleep Three: PMXMMX, XMXMMP, PMMXMX, XMMXMP
# Live Two: XMMX
# Sleep Two: PMMX, XMMP
if m_range == 2:
left_empty = right_empty = False
left_three = right_three = False
if line[left_idx-1] == empty:
if line[left_idx-2] == mine:
setRecord(self, x, y, left_idx-2, left_idx-1, dir_index, dir)
if line[left_idx-3] == empty:
if line[right_idx+1] == empty: # XMXMMX
count[THREE] += 1
else: # XMXMMP
count[STHREE] += 1
left_three = True
elif line[left_idx-3] == opponent: # PMXMMX
if line[right_idx+1] == empty:
count[STHREE] += 1
left_three = True
left_empty = True
if line[right_idx+1] == empty:
if line[right_idx+2] == mine:
if line[right_idx+3] == mine: # MMXMM
setRecord(self, x, y, right_idx+1, right_idx+2, dir_index, dir)
count[SFOUR] += 1
right_three = True
elif line[right_idx+3] == empty:
#setRecord(self, x, y, right_idx+1, right_idx+2, dir_index, dir)
if left_empty: # XMMXMX
count[THREE] += 1
else: # PMMXMX
count[STHREE] += 1
right_three = True
elif left_empty: # XMMXMP
count[STHREE] += 1
right_three = True
right_empty = True
if left_three or right_three:
pass
elif left_empty and right_empty: # XMMX
count[TWO] += 1
elif left_empty or right_empty: # PMMX, XMMP
count[STWO] += 1
# Live Two: XMXMX, XMXXMX only check right direction
# Sleep Two: PMXMX, XMXMP
if m_range == 1:
left_empty = right_empty = False
if line[left_idx-1] == empty:
if line[left_idx-2] == mine:
if line[left_idx-3] == empty:
if line[right_idx+1] == opponent: # XMXMP
count[STWO] += 1
left_empty = True
if line[right_idx+1] == empty:
if line[right_idx+2] == mine:
if line[right_idx+3] == empty:
if left_empty: # XMXMX
#setRecord(self, x, y, left_idx, right_idx+2, dir_index, dir)
count[TWO] += 1
else: # PMXMX
count[STWO] += 1
elif line[right_idx+2] == empty:
if line[right_idx+3] == mine and line[right_idx+4] == empty: # XMXXMX
count[TWO] += 1
return CHESS_TYPE.NONE
完整代碼
一共有三個文件，新增加了一個ChessAI.py。
main.py
增加了對於ChessAI類的 findBestChess 函數的調用，獲取AI選擇的下棋位置。
import pygame
from pygame.locals import *
from GameMap import *
from ChessAI import *
class Button():
def __init__(self, screen, text, x, y, color, enable):
self.screen = screen
self.width = BUTTON_WIDTH
self.height = BUTTON_HEIGHT
self.button_color = color
self.text_color = (255, 255, 255)
self.enable = enable
self.font = pygame.font.SysFont(None, BUTTON_HEIGHT*2//3)
self.rect = pygame.Rect(0, 0, self.width, self.height)
self.rect.topleft = (x, y)
self.text = text
self.init_msg()
def init_msg(self):
if self.enable:
self.msg_image = self.font.render(self.text, True, self.text_color, self.button_color[0])
else:
self.msg_image = self.font.render(self.text, True, self.text_color, self.button_color[1])
self.msg_image_rect = self.msg_image.get_rect()
self.msg_image_rect.center = self.rect.center
def draw(self):
if self.enable:
self.screen.fill(self.button_color[0], self.rect)
else:
self.screen.fill(self.button_color[1], self.rect)
self.screen.blit(self.msg_image, self.msg_image_rect)
class StartButton(Button):
def __init__(self, screen, text, x, y):
super().__init__(screen, text, x, y, [(26, 173, 25),(158, 217, 157)], True)
def click(self, game):
if self.enable:
game.start()
game.winner = None
self.msg_image = self.font.render(self.text, True, self.text_color, self.button_color[1])
self.enable = False
return True
return False
def unclick(self):
if not self.enable:
self.msg_image = self.font.render(self.text, True, self.text_color, self.button_color[0])
self.enable = True
class GiveupButton(Button):
def __init__(self, screen, text, x, y):
super().__init__(screen, text, x, y, [(230, 67, 64),(236, 139, 137)], False)
def click(self, game):
if self.enable:
game.is_play = False
if game.winner is None:
game.winner = game.map.reverseTurn(game.player)
self.msg_image = self.font.render(self.text, True, self.text_color, self.button_color[1])
self.enable = False
return True
return False
def unclick(self):
if not self.enable:
self.msg_image = self.font.render(self.text, True, self.text_color, self.button_color[0])
self.enable = True
class Game():
def __init__(self, caption):
pygame.init()
self.screen = pygame.display.set_mode([SCREEN_WIDTH, SCREEN_HEIGHT])
pygame.display.set_caption(caption)
self.clock = pygame.time.Clock()
self.buttons = []
self.buttons.append(StartButton(self.screen, 'Start', MAP_WIDTH + 30, 15))
self.buttons.append(GiveupButton(self.screen, 'Giveup', MAP_WIDTH + 30, BUTTON_HEIGHT + 45))
self.is_play = False
self.map = Map(CHESS_LEN, CHESS_LEN)
self.player = MAP_ENTRY_TYPE.MAP_PLAYER_ONE
self.action = None
self.AI = ChessAI(CHESS_LEN)
self.useAI = False
self.winner = None
def start(self):
self.is_play = True
self.player = MAP_ENTRY_TYPE.MAP_PLAYER_ONE
self.map.reset()
def play(self):
self.clock.tick(60)
light_yellow = (247, 238, 214)
pygame.draw.rect(self.screen, light_yellow, pygame.Rect(0, 0, MAP_WIDTH, SCREEN_HEIGHT))
pygame.draw.rect(self.screen, (255, 255, 255), pygame.Rect(MAP_WIDTH, 0, INFO_WIDTH, SCREEN_HEIGHT))
for button in self.buttons:
button.draw()
if self.is_play and not self.isOver():
if self.useAI:
x, y = self.AI.findBestChess(self.map.map, self.player)
self.checkClick(x, y, True)
self.useAI = False
if self.action is not None:
self.checkClick(self.action[0], self.action[1])
self.action = None
if not self.isOver():
self.changeMouseShow()
if self.isOver():
self.showWinner()
self.map.drawBackground(self.screen)
self.map.drawChess(self.screen)
def changeMouseShow(self):
map_x, map_y = pygame.mouse.get_pos()
x, y = self.map.MapPosToIndex(map_x, map_y)
if self.map.isInMap(map_x, map_y) and self.map.isEmpty(x, y):
pygame.mouse.set_visible(False)
light_red = (213, 90, 107)
pos, radius = (map_x, map_y), CHESS_RADIUS
pygame.draw.circle(self.screen, light_red, pos, radius)
else:
pygame.mouse.set_visible(True)
def checkClick(self,x, y, isAI=False):
self.map.click(x, y, self.player)
if self.AI.isWin(self.map.map, self.player):
self.winner = self.player
self.click_button(self.buttons[1])
else:
self.player = self.map.reverseTurn(self.player)
if not isAI:
self.useAI = True
def mouseClick(self, map_x, map_y):
if self.is_play and self.map.isInMap(map_x, map_y) and not self.isOver():
x, y = self.map.MapPosToIndex(map_x, map_y)
if self.map.isEmpty(x, y):
self.action = (x, y)
def isOver(self):
return self.winner is not None
def showWinner(self):
def showFont(screen, text, location_x, locaiton_y, height):
font = pygame.font.SysFont(None, height)
font_image = font.render(text, True, (0, 0, 255), (255, 255, 255))
font_image_rect = font_image.get_rect()
font_image_rect.x = location_x
font_image_rect.y = locaiton_y
screen.blit(font_image, font_image_rect)
if self.winner == MAP_ENTRY_TYPE.MAP_PLAYER_ONE:
str = 'Winner is White'
else:
str = 'Winner is Black'
showFont(self.screen, str, MAP_WIDTH + 25, SCREEN_HEIGHT - 60, 30)
pygame.mouse.set_visible(True)
def click_button(self, button):
if button.click(self):
for tmp in self.buttons:
if tmp != button:
tmp.unclick()
def check_buttons(self, mouse_x, mouse_y):
for button in self.buttons:
if button.rect.collidepoint(mouse_x, mouse_y):
self.click_button(button)
break
game = Game("FIVE CHESS " + GAME_VERSION)
while True:
game.play()
pygame.display.update()
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
exit()
elif event.type == pygame.MOUSEBUTTONDOWN:
mouse_x, mouse_y = pygame.mouse.get_pos()
game.mouseClick(mouse_x, mouse_y)
game.check_buttons(mouse_x, mouse_y)
GameMap.py
這個文件沒有修改，可以直接使用上一篇中的代碼。
ChessAI.py
AI實現的代碼，這個AI目前很簡單，只會思考一步，後續會增加思考的步數，比如2步或4步。
from GameMap import *
from enum import IntEnum
import copy
import time
class CHESS_TYPE(IntEnum):
NONE = 0,
SLEEP_TWO = 1,
LIVE_TWO = 2,
SLEEP_THREE = 3
LIVE_THREE = 4,
CHONG_FOUR = 5,
LIVE_FOUR = 6,
LIVE_FIVE = 7,
CHESS_TYPE_NUM = 8
FIVE = CHESS_TYPE.LIVE_FIVE.value
FOUR, THREE, TWO = CHESS_TYPE.LIVE_FOUR.value, CHESS_TYPE.LIVE_THREE.value, CHESS_TYPE.LIVE_TWO.value
SFOUR, STHREE, STWO = CHESS_TYPE.CHONG_FOUR.value, CHESS_TYPE.SLEEP_THREE.value, CHESS_TYPE.SLEEP_TWO.value
class ChessAI():
def __init__(self, chess_len):
self.len = chess_len
# [horizon, vertical, left diagonal, right diagonal]
self.record = [[[0,0,0,0] for x in range(chess_len)] for y in range(chess_len)]
self.count = [[0 for x in range(CHESS_TYPE_NUM)] for i in range(2)]
self.pos_score = [[(7 - max(abs(x - 7), abs(y - 7))) for x in range(chess_len)] for y in range(chess_len)]
def reset(self):
for y in range(self.len):
for x in range(self.len):
for i in range(4):
self.record[y][x][i] = 0
for i in range(len(self.count)):
for j in range(len(self.count[0])):
self.count[i][j] = 0
self.save_count = 0
def isWin(self, board, turn):
return self.evaluate(board, turn, True)
# get all positions that is empty
def genmove(self, board, turn):
moves = []
for y in range(self.len):
for x in range(self.len):
if board[y][x] == 0:
score = self.pos_score[y][x]
moves.append((score, x, y))
moves.sort(reverse=True)
return moves
def search(self, board, turn):
moves = self.genmove(board, turn)
bestmove = None
max_score = -0x7fffffff
for score, x, y in moves:
board[y][x] = turn.value
score = self.evaluate(board, turn)
board[y][x] = 0
if score > max_score:
max_score = score
bestmove = (max_score, x, y)
return bestmove
def findBestChess(self, board, turn):
time1 = time.time()
score, x, y = self.search(board, turn)
time2 = time.time()
print('time[%f] (%d, %d), score[%d] save[%d]' % ((time2-time1), x, y, score, self.save_count))
return (x, y)
# calculate score, FIXME: May Be Improved
def getScore(self, mine_count, opponent_count):
mscore, oscore = 0, 0
if mine_count[FIVE] > 0:
return (10000, 0)
if opponent_count[FIVE] > 0:
return (0, 10000)
if mine_count[SFOUR] >= 2:
mine_count[FOUR] += 1
if opponent_count[FOUR] > 0:
return (0, 9050)
if opponent_count[SFOUR] > 0:
return (0, 9040)
if mine_count[FOUR] > 0:
return (9030, 0)
if mine_count[SFOUR] > 0 and mine_count[THREE] > 0:
return (9020, 0)
if opponent_count[THREE] > 0 and mine_count[SFOUR] == 0:
return (0, 9010)
if (mine_count[THREE] > 1 and opponent_count[THREE] == 0 and opponent_count[STHREE] == 0):
return (9000, 0)
if mine_count[SFOUR] > 0:
mscore += 2000
if mine_count[THREE] > 1:
mscore += 500
elif mine_count[THREE] > 0:
mscore += 100
if opponent_count[THREE] > 1:
oscore += 2000
elif opponent_count[THREE] > 0:
oscore += 400
if mine_count[STHREE] > 0:
mscore += mine_count[STHREE] * 10
if opponent_count[STHREE] > 0:
oscore += opponent_count[STHREE] * 10
if mine_count[TWO] > 0:
mscore += mine_count[TWO] * 4
if opponent_count[TWO] > 0:
oscore += opponent_count[TWO] * 4
if mine_count[STWO] > 0:
mscore += mine_count[STWO] * 4
if opponent_count[STWO] > 0:
oscore += opponent_count[STWO] * 4
return (mscore, oscore)
def evaluate(self, board, turn, checkWin=False):
self.reset()
if turn == MAP_ENTRY_TYPE.MAP_PLAYER_ONE:
mine = 1
opponent = 2
else:
mine = 2
opponent = 1
for y in range(self.len):
for x in range(self.len):
if board[y][x] == mine:
self.evaluatePoint(board, x, y, mine, opponent)
elif board[y][x] == opponent:
self.evaluatePoint(board, x, y, opponent, mine)
mine_count = self.count[mine-1]
opponent_count = self.count[opponent-1]
if checkWin:
return mine_count[FIVE] > 0
else:
mscore, oscore = self.getScore(mine_count, opponent_count)
return (mscore - oscore)
def evaluatePoint(self, board, x, y, mine, opponent):
dir_offset = [(1, 0), (0, 1), (1, 1), (1, -1)] # direction from left to right
for i in range(4):
if self.record[y][x][i] == 0:
self.analysisLine(board, x, y, i, dir_offset[i], mine, opponent, self.count[mine-1])
else:
self.save_count += 1
# line is fixed len 9: XXXXMXXXX
def getLine(self, board, x, y, dir_offset, mine, opponent):
line = [0 for i in range(9)]
tmp_x = x + (-5 * dir_offset[0])
tmp_y = y + (-5 * dir_offset[1])
for i in range(9):
tmp_x += dir_offset[0]
tmp_y += dir_offset[1]
if (tmp_x < 0 or tmp_x >= self.len or
tmp_y < 0 or tmp_y >= self.len):
line[i] = opponent # set out of range as opponent chess
else:
line[i] = board[tmp_y][tmp_x]
return line
def analysisLine(self, board, x, y, dir_index, dir, mine, opponent, count):
def setRecord(self, x, y, left, right, dir_index, dir_offset):
tmp_x = x + (-5 + left) * dir_offset[0]
tmp_y = y + (-5 + left) * dir_offset[1]
for i in range(left, right):
tmp_x += dir_offset[0]
tmp_y += dir_offset[1]
self.record[tmp_y][tmp_x][dir_index] = 1
empty = MAP_ENTRY_TYPE.MAP_EMPTY.value
left_idx, right_idx = 4, 4
line = self.getLine(board, x, y, dir, mine, opponent)
while right_idx < 8:
if line[right_idx+1] != mine:
break
right_idx += 1
while left_idx > 0:
if line[left_idx-1] != mine:
break
left_idx -= 1
left_range, right_range = left_idx, right_idx
while right_range < 8:
if line[right_range+1] == opponent:
break
right_range += 1
while left_range > 0:
if line[left_range-1] == opponent:
break
left_range -= 1
chess_range = right_range - left_range + 1
if chess_range < 5:
setRecord(self, x, y, left_range, right_range, dir_index, dir)
return CHESS_TYPE.NONE
setRecord(self, x, y, left_idx, right_idx, dir_index, dir)
m_range = right_idx - left_idx + 1
# M:mine chess, P:opponent chess or out of range, X: empty
if m_range == 5:
count[FIVE] += 1
# Live Four : XMMMMX
# Chong Four : XMMMMP, PMMMMX
if m_range == 4:
left_empty = right_empty = False
if line[left_idx-1] == empty:
left_empty = True
if line[right_idx+1] == empty:
right_empty = True
if left_empty and right_empty:
count[FOUR] += 1
elif left_empty or right_empty:
count[SFOUR] += 1
# Chong Four : MXMMM, MMMXM, the two types can both exist
# Live Three : XMMMXX, XXMMMX
# Sleep Three : PMMMX, XMMMP, PXMMMXP
if m_range == 3:
left_empty = right_empty = False
left_four = right_four = False
if line[left_idx-1] == empty:
if line[left_idx-2] == mine: # MXMMM
setRecord(self, x, y, left_idx-2, left_idx-1, dir_index, dir)
count[SFOUR] += 1
left_four = True
left_empty = True
if line[right_idx+1] == empty:
if line[right_idx+2] == mine: # MMMXM
setRecord(self, x, y, right_idx+1, right_idx+2, dir_index, dir)
count[SFOUR] += 1
right_four = True
right_empty = True
if left_four or right_four:
pass
elif left_empty and right_empty:
if chess_range > 5: # XMMMXX, XXMMMX
count[THREE] += 1
else: # PXMMMXP
count[STHREE] += 1
elif left_empty or right_empty: # PMMMX, XMMMP
count[STHREE] += 1
# Chong Four: MMXMM, only check right direction
# Live Three: XMXMMX, XMMXMX the two types can both exist
# Sleep Three: PMXMMX, XMXMMP, PMMXMX, XMMXMP
# Live Two: XMMX
# Sleep Two: PMMX, XMMP
if m_range == 2:
left_empty = right_empty = False
left_three = right_three = False
if line[left_idx-1] == empty:
if line[left_idx-2] == mine:
setRecord(self, x, y, left_idx-2, left_idx-1, dir_index, dir)
if line[left_idx-3] == empty:
if line[right_idx+1] == empty: # XMXMMX
count[THREE] += 1
else: # XMXMMP
count[STHREE] += 1
left_three = True
elif line[left_idx-3] == opponent: # PMXMMX
if line[right_idx+1] == empty:
count[STHREE] += 1
left_three = True
left_empty = True
if line[right_idx+1] == empty:
if line[right_idx+2] == mine:
if line[right_idx+3] == mine: # MMXMM
setRecord(self, x, y, right_idx+1, right_idx+2, dir_index, dir)
count[SFOUR] += 1
right_three = True
elif line[right_idx+3] == empty:
#setRecord(self, x, y, right_idx+1, right_idx+2, dir_index, dir)
if left_empty: # XMMXMX
count[THREE] += 1
else: # PMMXMX
count[STHREE] += 1
right_three = True
elif left_empty: # XMMXMP
count[STHREE] += 1
right_three = True
right_empty = True
if left_three or right_three:
pass
elif left_empty and right_empty: # XMMX
count[TWO] += 1
elif left_empty or right_empty: # PMMX, XMMP
count[STWO] += 1
# Live Two: XMXMX, XMXXMX only check right direction
# Sleep Two: PMXMX, XMXMP
if m_range == 1:
left_empty = right_empty = False
if line[left_idx-1] == empty:
if line[left_idx-2] == mine:
if line[left_idx-3] == empty:
if line[right_idx+1] == opponent: # XMXMP
count[STWO] += 1
left_empty = True
if line[right_idx+1] == empty:
if line[right_idx+2] == mine:
if line[right_idx+3] == empty:
if left_empty: # XMXMX
#setRecord(self, x, y, left_idx, right_idx+2, dir_index, dir)
count[TWO] += 1
else: # PMXMX
count[STWO] += 1
elif line[right_idx+2] == empty:
if line[right_idx+3] == mine and line[right_idx+4] == empty: # XMXXMX
count[TWO] += 1
return CHESS_TYPE.NONE