python贪吃蛇游戏项目-自动化贪吃蛇理论-2

def bfs_agent(self,env):
        """用 BFS 找到蛇头到食物的最短路径，返回第一个动作"""
        head = (int(env.snake_x), int(env.snake_y))
        food = (int(env.food_x), int(env.food_y))
        snake_body = set(map(tuple, env.snake_list))  # 把蛇身体当成障碍

        directions = {
            0: (0, -env.snake_block),   # up
            1: (0, env.snake_block),    # down
            2: (-env.snake_block, 0),   # left
            3: (env.snake_block, 0)     # right
        }

        queue = deque([(head, [])])
        visited = {head}

        while queue:
            (x, y), path = queue.popleft()

            # 找到食物，返回路径的第一个动作
            if (x, y) == food:
                return path[0] if path else random.choice([0, 1, 2, 3])

            for action, (dx, dy) in directions.items():
                nx, ny = x + dx, y + dy
                # 边界检查
                if 0 <= nx < env.window_width and 0 <= ny < env.window_height:
                    if (nx, ny) not in snake_body and (nx, ny) not in visited:
                        visited.add((nx, ny))
                        queue.append(((nx, ny), path + [action]))

        # 如果没有路径，随机走一步
        return random.choice([0, 1, 2, 3])