用DFS写一个自动贪吃蛇小游戏

以下是用DFS（深度优先搜索）实现自动贪吃蛇小游戏的示例代码：

import pygame
import random

# 定义游戏区域大小和每个格子大小
SCREEN_WIDTH = 400
SCREEN_HEIGHT = 400
GRID_SIZE = 20

# 定义颜色
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
RED = (255, 0, 0)
GREEN = (0, 255, 0)

# 定义方向常量
UP = 1
DOWN = 2
LEFT = 3
RIGHT = 4

# 定义贪吃蛇类
class Snake:
    def __init__(self):
        self.body = [(10, 10), (10, 11), (10, 12)]  # 初始位置为 (10, 10), (10, 11), (10, 12)
        self.direction = RIGHT  # 初始方向向右
        self.color = GREEN

    def move(self):
        # 根据方向移动蛇头
        head = self.body[-1]
        if self.direction == UP:
            self.body.append((head[0], head[1] - 1))
        elif self.direction == DOWN:
            self.body.append((head[0], head[1] + 1))
        elif self.direction == LEFT:
            self.body.append((head[0] - 1, head[1]))
        elif self.direction == RIGHT:
            self.body.append((head[0] + 1, head[1]))

        # 删除尾部，即蛇尾部分
        self.body.pop(0)

    def change_direction(self, direction):
        # 防止蛇头掉头
        if self.direction == UP and direction == DOWN:
            return
        elif self.direction == DOWN and direction == UP:
            return
        elif self.direction == LEFT and direction == RIGHT:
            return
        elif self.direction == RIGHT and direction == LEFT:
            return

        # 修改方向
        self.direction = direction

    def draw(self, surface):
        # 绘制蛇的每一节
        for i, pos in enumerate(self.body):
            pygame.draw.rect(surface, self.color, (pos[0] * GRID_SIZE, pos[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE))
            pygame.draw.rect(surface, BLACK, (pos[0] * GRID_SIZE, pos[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE), 1)


# 定义食物类
class Food:
    def __init__(self):
        self.pos = (0, 0)  # 食物的初始位置
        self.color = RED

    def generate(self, snake_body):
        # 生成一个新的食物位置
        while True:
            x = random.randint(0, SCREEN_WIDTH // GRID_SIZE - 1)
            y = random.randint(0, SCREEN_HEIGHT // GRID_SIZE - 1)
            if (x, y) not in snake_body:
                self.pos = (x, y)
                break

    def draw(self, surface):
        # 绘制食物
        pygame.draw.rect(surface, self.color, (self.pos[0] * GRID_SIZE, self.pos[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE))


# 定义游戏主函数
def main():
    # 初始化 pygame
    pygame.init()

    # 创建游戏窗口
    screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))

    # 创建贪吃蛇
    snake = Snake()

    # 创建食物
    food = Food()
    food.generate(snake.body)

    # 设置游戏帧率
    clock = pygame.time.Clock()

    # 游戏主循环
    while True:
        # 处理事件
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()
                exit()
            elif event.type == pygame.KEYDOWN:
                if event.key == pygame.K_UP:
                    snake.change_direction(UP)
                elif event.key == pygame.K_DOWN:
                    snake.change_direction(DOWN)
                elif event.key == pygame.K_LEFT:
                    snake.change_direction(LEFT)
                elif event.key == pygame.K_RIGHT:
                    snake.change_direction(RIGHT)

        # 移动贪吃蛇
        snake.move()

        # 判断是否吃到食物
        if snake.body[-1] == food.pos:
            food.generate(snake.body)
            snake.body.insert(0, snake.body[0])

        # 绘制背景和游戏元素
        screen.fill(WHITE)
        snake.draw(screen)
        food.draw(screen)

        # 更新屏幕
        pygame.display.update()

        # 控制帧率
        clock.tick(10)

if __name__ == '__main__':
    main()

以上代码实现了一个基本的贪吃蛇游戏，通过键盘控制蛇的方向。如果要使用DFS实现自动贪吃蛇，可以考虑在每次移动之前，通过DFS搜索下一步的最佳方向，然后再移动蛇。具体实现方法可以参考一些相关的文章和代码。