def minvalue(self, depth, state, alpha, beta):
self.depthLvl += 1
isDone = CheckerBoard.is_terminal(state)
if isDone[0]:
v = self.strategy.utility(state) #if terminal state
elif self.depthLvl >= depth: #if cutoff depth hit
v = float('inf')
actions = state.get_actions(self.maxP)
for a in actions: #choose move at depth
newboard = state.move(a)
w = self.strategy.utility(newboard)
v = min(v, w)
else: #if neither, then keep searching
v = float("inf")
actions = state.get_actions(self.minP)
for a in actions:
newboard = state.move(a)
v = min(v, self.maxvalue(depth, newboard, alpha, beta))
if v <= alpha:
break
else:
beta = max(alpha, v)
return v
def Game(red=ai.Strategy, black=tonto.Strategy,
maxplies=5, init=None, verbose=True, firstmove=0):
"""Game(red, black, maxplies, init, verbose, turn)
Start a game of checkers
red,black - Strategy classes (not instances)
maxplies - # of turns to explore (default 10)
init - Start with given board (default None uses a brand new game)
verbose - Show messages (default True)
firstmove - Player N starts 0 (red) or 1 (black). Default 0.
"""
# Don't forget to create instances of your strategy,
# e.g. black('b', checkerboard.CheckerBoard, maxplies)
### Still unsure what firstmove is supposed to do ###
# Initialize board
if init is None:
board = CheckerBoard() # New game
else:
board = init # Initialize board to given config
# Display Board
if verbose:
print('Initial Board:')
print(board, '\n')
# Initialize Players
red = red('r', board, maxplies)
black = black('b', board, maxplies)
# Start playing
while not board.is_terminal()[0]: # Nobody has won yet
state = red.play(board) # Get tuple of new board following an action and the action itself
board = state[0]
action = state[1]
if verbose and action is not None:
print('Red Move: ', board.get_action_str(action))
print(board)
# Player has forfeited -> exit loop
if action is None:
print('Red Player has forfeited the game')
break
if not board.is_terminal()[0]: # Still nobody has won yet
state = black.play(board) # Get tuple of new board following an action and the action itself
board = state[0]
action = state[1]
if verbose and action is not None:
print('Black Move: ', board.get_action_str(action))
print(board)
# Player has forfeited -> exit loop
if action is None:
print('Black Player has forfeited the game')
break
if (board.is_terminal()[1] == 'r'):
print('Red Player wins')
elif (board.is_terminal()[1] == 'b'):
print('Black Player wins')
else:
print('Game has ended in a stalemate')