generated from mwc/lab_tic_tac_toe
85 lines
3.4 KiB
Python
85 lines
3.4 KiB
Python
class TTTGame:
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"Models a tic-tac-toe game."
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def get_initial_state(self):
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"Returns the game's initial state."
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return {
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"board": ['-', '-', '-', '-', '-', '-', '-', '-', '-'],
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"player_x": True,
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}
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def get_next_state(self, state, action):
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"""Given a state and an action, returns the resulting state.
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In the resulting state, the current player's symbol has been placed
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in an empty board space, and it is the opposite player's turn.
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"""
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new_board = state["board"].copy()
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new_board[action] = 'X' if state["player_x"] else 'O'
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return {
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"board": new_board,
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"player_x": not state["player_x"],
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}
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def get_actions(self, state):
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"Returns a list of the indices of empty spaces"
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return [index for index in range(9) if state["board"][index] == '-']
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def is_over(self, state):
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"Checks whether the game is over."
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return self.board_is_full(state) or self.check_winner(state, 'X') or self.check_winner(state, 'O')
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def get_reward(self, state):
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"""Determines the reward associated with reaching this state.
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For tic-tac-toe, the two opponents each want a different game outcome. So
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we set the reward for X winning to 1 and the reward for O winning to -1.
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All other states (unfinished games and games which ended in a draw) are worth 0.
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"""
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if self.check_winner(state, 'X'):
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return 1
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elif self.check_winner(state, 'O'):
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return -1
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else:
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return 0
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def get_objective(self, state):
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"""Returns a player's objective, or a function describing what a player wants.
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This function should choose the best value from a list. In tic tac toe, the players
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want opposite things, so we set X's objective to the built-in function `max`
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(which chooses the largest number), and we set O's objective to the built-in function `min`.
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"""
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return max if state["player_x"] else min
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def board_is_full(self, state):
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"Checks whether all the spaces in the board are occupied."
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for space in state["board"]:
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if space == '-':
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return False
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return True
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def check_winner(self, state, symbol):
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"Checks whether the player with `symbol` has won the game."
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"""Seems to be an issue because the code looks incomplete.
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In the View, it shows the Player's choice/symbol placed on the Tic Tac Toe
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board as a winner, but doesn't announce the Player as the winner, the Game
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keeps playing as though there is no winner. The Game doesn't recognize that the
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Player has "3 symbols in a row," this should stop the game to determine the winner.
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The Game doesn't state in the "View" that the current Player is the winner.
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"""
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board = state["board"]
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for row in range(3):
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if all(board[row * 3 + col] == symbol for col in range(3)):
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return True
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for col in range(3):
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if all(board[row + col * 3] == symbol for row in range(3)):
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return True
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if board[0] == board[4] == board[8] == symbol or board[2] == board[4] == board[6] == symbol:
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return True
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return False
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"""I played the game.
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Message
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Well, that's a wrap.
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Congratulations to Player 1.
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"""
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