diff -r 44383203970f -r e2170c91a9f2 pre_marking3/postfix_test1.scala
--- a/pre_marking3/postfix_test1.scala	Fri Jan 15 02:47:51 2021 +0000
+++ b/pre_marking3/postfix_test1.scala	Mon Jan 18 22:12:39 2021 +0000
@@ -1,4 +1,4 @@
-import CW9a._
+import CW8a._
 
 
 assert(syard(split("3 + 4 * ( 2 - 1 )")) == List("3", "4", "2", "1", "-", "*", "+"))