save project

snake.py

@@ -65,6 +65,8 @@ while True:
         score+=10
         score+=10
     else:
     else:
         position.pop(0)
         position.pop(0)
+    if x<0 or x>630 or y<0 or y>450:
+        quit()
     position.append((x, y))# 将背景图画上去
     position.append((x, y))# 将背景图画上去
     screen.blit(background, (0, 0))
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去
     # 将贪吃蛇的头画上去