|
| 1 | +import random |
| 2 | +import copy |
| 3 | + |
| 4 | +class AI2048: |
| 5 | + def __init__(self, board): |
| 6 | + self.board = board |
| 7 | + |
| 8 | + def get_empty_cells(self): |
| 9 | + empty_cells = [] |
| 10 | + for i in range(len(self.board)): |
| 11 | + for j in range(len(self.board[i])): |
| 12 | + if self.board[i][j] == 0: |
| 13 | + empty_cells.append((i, j)) |
| 14 | + return empty_cells |
| 15 | + |
| 16 | + def get_max_tile(self): |
| 17 | + return max(map(max, self.board)) |
| 18 | + |
| 19 | + def move_left(self): |
| 20 | + merged = [] |
| 21 | + for row in self.board: |
| 22 | + new_row = [tile for tile in row if tile != 0] |
| 23 | + for i in range(len(new_row) - 1): |
| 24 | + if new_row[i] == new_row[i + 1]: |
| 25 | + new_row[i] *= 2 |
| 26 | + new_row[i + 1] = 0 |
| 27 | + merged.append(new_row[i]) |
| 28 | + new_row = [tile for tile in new_row if tile != 0] |
| 29 | + new_row.extend([0] * (len(row) - len(new_row))) |
| 30 | + self.board[self.board.index(row)] = new_row |
| 31 | + return merged |
| 32 | + |
| 33 | + def move_right(self): |
| 34 | + self.flip_board() |
| 35 | + merged = self.move_left() |
| 36 | + self.flip_board() |
| 37 | + return merged |
| 38 | + |
| 39 | + def move_up(self): |
| 40 | + self.transpose_board() |
| 41 | + merged = self.move_left() |
| 42 | + self.transpose_board() |
| 43 | + return merged |
| 44 | + |
| 45 | + def move_down(self): |
| 46 | + self.transpose_board() |
| 47 | + merged = self.move_right() |
| 48 | + self.transpose_board() |
| 49 | + return merged |
| 50 | + |
| 51 | + def get_score(self): |
| 52 | + return sum(map(sum, self.board)) |
| 53 | + |
| 54 | + def get_heuristic_score(self): |
| 55 | + max_tile = self.get_max_tile() |
| 56 | + empty_cells = len(self.get_empty_cells()) |
| 57 | + smoothness = self.calculate_smoothness() |
| 58 | + monotonicity = self.calculate_monotonicity() |
| 59 | + |
| 60 | + # Weighted sum of different heuristics |
| 61 | + return 0.1 * self.get_score() + 2.7 * empty_cells + 1.0 * smoothness + 1.5 * monotonicity + 3.0 * max_tile |
| 62 | + |
| 63 | + def calculate_smoothness(self): |
| 64 | + smoothness = 0 |
| 65 | + for i in range(len(self.board)): |
| 66 | + for j in range(len(self.board[i])): |
| 67 | + if self.board[i][j] != 0: |
| 68 | + value = math.log2(self.board[i][j]) |
| 69 | + for (dx, dy) in [(-1, 0), (0, -1), (1, 0), (0, 1)]: |
| 70 | + x, y = i + dx, j + dy |
| 71 | + if 0 <= x < len(self.board) and 0 <= y < len(self.board[i]) and self.board[x][y] != 0: |
| 72 | + neighbor_value = math.log2(self.board[x][y]) |
| 73 | + smoothness -= abs(value - neighbor_value) |
| 74 | + return smoothness |
| 75 | + |
| 76 | + def calculate_monotonicity(self): |
| 77 | + monotonicity = [0, 0, 0, 0] |
| 78 | + for i in range(len(self.board)): |
| 79 | + current = 0 |
| 80 | + next = current + 1 |
| 81 | + while next < 4: |
| 82 | + while next < 4 and self.board[i][next] == 0: |
| 83 | + next += 1 |
| 84 | + if next >= 4: |
| 85 | + next -= 1 |
| 86 | + current_value = 0 if self.board[i][current] == 0 else math.log2(self.board[i][current]) |
| 87 | + next_value = 0 if self.board[i][next] == 0 else math.log2(self.board[i][next]) |
| 88 | + if current_value > next_value: |
| 89 | + monotonicity[0] += next_value - current_value |
| 90 | + elif next_value > current_value: |
| 91 | + monotonicity[1] += current_value - next_value |
| 92 | + current = next |
| 93 | + next += 1 |
| 94 | + |
| 95 | + for j in range(len(self.board[0])): |
| 96 | + current = 0 |
| 97 | + next = current + 1 |
| 98 | + while next < 4: |
| 99 | + while next < 4 and self.board[next][j] == 0: |
| 100 | + next += 1 |
| 101 | + if next >= 4: |
| 102 | + next -= 1 |
| 103 | + current_value = 0 if self.board[current][j] == 0 else math.log2(self.board[current][j]) |
| 104 | + next_value = 0 if self.board[next][j] == 0 else math.log2(self.board[next][j]) |
| 105 | + if current_value > next_value: |
| 106 | + monotonicity[2] += next_value - current_value |
| 107 | + elif next_value > current_value: |
| 108 | + monotonicity[3] += current_value - next_value |
| 109 | + current = next |
| 110 | + next += 1 |
| 111 | + |
| 112 | + return max(monotonicity) |
| 113 | + |
| 114 | + def get_children_states(self): |
| 115 | + children = [] |
| 116 | + for move in ['left', 'right', 'up', 'down']: |
| 117 | + new_board = copy.deepcopy(self.board) |
| 118 | + merged = self.move(new_board, move) |
| 119 | + if merged: |
| 120 | + children.append((new_board, merged)) |
| 121 | + return children |
| 122 | + |
| 123 | + def get_best_move(self, depth=3): |
| 124 | + moves = ['left', 'right', 'up', 'down'] |
| 125 | + best_score = float('-inf') |
| 126 | + best_move = random.choice(moves) |
| 127 | + for move in moves: |
| 128 | + new_board = copy.deepcopy(self.board) |
| 129 | + merged = self.move(new_board, move) |
| 130 | + if merged: |
| 131 | + child = AI2048(new_board) |
| 132 | + score = self.expectimax(child, depth - 1, False) |
| 133 | + if score > best_score: |
| 134 | + best_score = score |
| 135 | + best_move = move |
| 136 | + return best_move |
| 137 | + |
| 138 | + def expectimax(self, node, depth, is_maximizing): |
| 139 | + if depth == 0: |
| 140 | + return node.get_heuristic_score() |
| 141 | + |
| 142 | + if is_maximizing: |
| 143 | + max_eval = float('-inf') |
| 144 | + children = node.get_children_states() |
| 145 | + for child_board, merged in children: |
| 146 | + child = AI2048(child_board) |
| 147 | + eval = self.expectimax(child, depth - 1, False) |
| 148 | + max_eval = max(max_eval, eval) |
| 149 | + return max_eval |
| 150 | + else: |
| 151 | + total_score = 0 |
| 152 | + empty_cells = node.get_empty_cells() |
| 153 | + for cell in empty_cells: |
| 154 | + child_board = copy.deepcopy(node.board) |
| 155 | + child_board[cell[0]][cell[1]] = 2 |
| 156 | + child = AI2048(child_board) |
| 157 | + eval = self.expectimax(child, depth - 1, True) |
| 158 | + total_score += eval |
| 159 | + return total_score / len(empty_cells) |
| 160 | + |
| 161 | + def move(self, board, direction): |
| 162 | + merged = [] |
| 163 | + if direction == 'left': |
| 164 | + merged = self.move_left(board) |
| 165 | + elif direction == 'right': |
| 166 | + merged = self.move_right(board) |
| 167 | + elif direction == 'up': |
| 168 | + merged = self.move_up(board) |
| 169 | + elif direction == 'down': |
| 170 | + merged = self.move_down(board) |
| 171 | + return merged |
| 172 | + |
| 173 | + def move_left(self, board): |
| 174 | + merged = [] |
| 175 | + for row in board: |
| 176 | + new_row = [tile for tile in row if tile != 0] |
| 177 | + for i in range(len(new_row) - 1): |
| 178 | + if new_row[i] == new_row[i + 1]: |
| 179 | + new_row[i] *= 2 |
| 180 | + new_row[i + 1] = 0 |
| 181 | + merged.append(new_row[i]) |
| 182 | + new_row = [tile for tile in new_row if tile != 0] |
| 183 | + new_row.extend([0] * (len(row) - len(new_row))) |
| 184 | + board[board.index(row)] = new_row |
| 185 | + return merged |
| 186 | + |
| 187 | + def move_right(self, board): |
| 188 | + self.flip_board(board) |
| 189 | + merged = self.move_left(board) |
| 190 | + self.flip_board(board) |
| 191 | + return merged |
| 192 | + |
| 193 | + def move_up(self, board): |
| 194 | + self.transpose_board(board) |
| 195 | + merged = self.move_left(board) |
| 196 | + self.transpose_board(board) |
| 197 | + return merged |
| 198 | + |
| 199 | + def move_down(self, board): |
| 200 | + self.transpose_board(board) |
| 201 | + merged = self.move_right(board) |
| 202 | + self.transpose_board(board) |
| 203 | + return merged |
| 204 | + |
| 205 | + def flip_board(self, board): |
| 206 | + for row in board: |
| 207 | + row.reverse() |
| 208 | + |
| 209 | + def transpose_board(self, board): |
| 210 | + board[:] = [list(i) for i in zip(*board)] |
| 211 | + |
| 212 | +def print_board(board): |
| 213 | + for row in board: |
| 214 | + print(row) |
| 215 | + print() |
| 216 | + |
| 217 | +if __name__ == "__main__": |
| 218 | + board = [ |
| 219 | + [0, 2, 2, 4], |
| 220 | + [0, 2, 0, 4], |
| 221 | + [0, 4, 2, 0], |
| 222 | + [0, 0, 2, 2] |
| 223 | + ] |
| 224 | + |
| 225 | + ai = AI2048(board) |
| 226 | + print("Initial Board:") |
| 227 | + print_board(ai.board) |
| 228 | + |
| 229 | + while True: |
| 230 | + if ai.get_empty_cells(): |
| 231 | + move = ai.get_best_move() |
| 232 | + print(f"Moving {move}") |
| 233 | + ai.move(move) |
| 234 | + print_board(ai.board) |
| 235 | + else: |
| 236 | + print("No more moves possible.") |
| 237 | + break |
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