save project

snake.py

@@ -25,6 +25,7 @@ apple_y = 300
 
 setheading = "right"
 snake_head = right
+score = 0
 
 while True:
     for event in pygame.event.get():
@@ -62,6 +63,8 @@ while True:
         apple_y = num2*30-30
 
     position.pop(0)
+    if x < 0 or x > 630 or y < 0 or y > 480:
+        exit()
     # 将背景图画上去
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去