2 files changed, 3 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore
index d35bc6f..709c382 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 *.ghc
 a.out
 runtest
+tags
diff --git a/README.md b/README.md
index 24e1336..0399ebd 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,8 @@ $ make
 
 ## Bonus
 
+**You need to `make fclean` when switching from all to bonus**.
+
 ```sh
 $ make bonus
 ```