diff --git a/CPP/README.md b/CPP/README.md
index b1d5cb2..df8c705 100644
--- a/CPP/README.md
+++ b/CPP/README.md
@@ -9,4 +9,4 @@
 * [map](https://github.com/hao14293/2020-Postgraduate-408/blob/master/CPP/map.md)
 * [stack](https://github.com/hao14293/2020-Postgraduate-408/blob/master/CPP/stack.md)
 
-### 3.
+