diff --git a/hws/01_spotify_playlists/README.md b/hws/01_spotify_playlists/README.md
index 862ca99..72b65dd 100644
--- a/hws/01_spotify_playlists/README.md
+++ b/hws/01_spotify_playlists/README.md
@@ -145,6 +145,7 @@ Use good coding style when you design and implement your program. Organize your
    - No reflection. (-1)
  - STL Vector & String (3 pts)
    - did not use STL vector (-3)
+   - did not use STL string (-3)
  - Program Structure (7 pts)
    - No credit (significantly incomplete implementation) (-7)
    - Putting almost everything in the main function. It's better to create separate functions for different tasks. (-2)