def MinMaxMidEndImproved(board, depth):
numBlack = MorrisGame.countNums(board.position)[1]
if depth == 0 or numBlack < 3:
board.value = staticMidEndImproved(board.position, depth)
MorrisGame.numEvaluate += 1
return board
else:
board.child = MorrisGame.genMoveMidEndBlack(board.position)
minValue = float('inf')
retBoard = None
for child in board.child:
result = MaxMinMidEndImproved(child, depth - 1)
if minValue > result.value:
minValue = result.value
retBoard = child
retBoard.value = minValue
return retBoard
def MinMaxMidEnd(board, depth):
""" use MINIMAX algorithm to choose the move for 'MIN' """
numBlack = MorrisGame.countNums(board.position)[1]
if depth == 0 or numBlack < 3:
board.value = MorrisGame.staticMidEnd(board.position)
MorrisGame.numEvaluate += 1
return board
else:
board.child = MorrisGame.genMoveMidEndBlack(board.position)
minValue = float('inf')
retBoard = None
for child in board.child:
result = MaxMinMidEnd(child, depth - 1)
if minValue > result.value:
# retBoard = result # for test
minValue = result.value
retBoard = child
retBoard.value = minValue
return retBoard
def MinMaxABMidEnd(board, depth, alpha, beta):
""" use Alpha-Beta pruning to choose the move for 'MIN' """
numBlack = MorrisGame.countNums(board.position)[1]
if depth == 0 or numBlack < 3:
board.value = MorrisGame.staticMidEnd(board.position)
MorrisGame.numEvaluate += 1
return board
else:
board.child = MorrisGame.genMoveMidEndBlack(board.position)
minValue = float('inf')
retBoard = None
for child in board.child:
result = MaxMinABMidEnd(child, depth - 1, alpha, beta)
if minValue > result.value:
minValue = result.value
retBoard = child
retBoard.value = minValue
if minValue <= alpha:
return retBoard
elif minValue < beta:
beta = minValue
return retBoard
