save project

snake.py

@@ -60,7 +60,8 @@ while True:
         apple_x=30*num1
         apple_x=30*num1
 
 
         apple_y=30*num2
         apple_y=30*num2
-    position.pop(0)
+    else:
+        position.pop(0)
     # 将背景图画上去
     # 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