diff --git a/KissFlow/Level1.md b/KissFlow/Level1.md
index 7cdb153..17047a9 100644
--- a/KissFlow/Level1.md
+++ b/KissFlow/Level1.md
@@ -46,8 +46,8 @@ Postfix Expression:
     void Postfix(struct Node* head){
       if(head!=null){
         postfix(head->left);
-        printf("%d ",head->value);
         postfix(head->right);
+        printf("%d ",head->value);
       }
     }