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snake.py

@@ -52,7 +52,10 @@ while True:
     else:
         y += 30
     position.append((x, y))
-    position.pop(0)
+
+    else:
+        position.pop(0)
+
     # 将背景图画上去
     screen.blit(background, (0, 0))
     # 将贪吃蛇的头画上去