def player_from_number(count):
modifier = signum(count)
if modifier == 0:
return None
return 'w' if modifier == 1 else 'b'
def verify_move(board, position, distance, player):
distance = distance * player_modifier(player)
new_position = position + distance
if position not in board_range() \
and position != jail_field(player):
return False
if distance not in valid_distance(player):
return False
if position in board_range() \
and signum(board[position]) != player_modifier(player):
return False
if position == jail_field(player) \
and board[jail_field(player)] == 0:
return False
if board[jail_field(player)] and position != jail_field(player):
return False
if goes_offboard(player, new_position):
for field in board[non_home_fields(player)]:
if player_from_number(field) == player:
return False
if not goes_offboard(player, new_position) \
and board[new_position] * player_modifier(enemy(player)) > 1:
return False
return True
def make_move(board, position, distance, player):
if not verify_move(board, position, distance, player):
return None
new_position = position + distance * player_modifier(player)
board = board.copy()
checker = player_modifier(player)
board[position] -= checker
if new_position in board_range():
if signum(board[new_position] == player_modifier(enemy(player))):
board[jail_field(enemy(player))] += board[new_position]
board[new_position] = 0
board[new_position] += checker
return board