diff --git a/content/docs/Cpp/hello-world/index.org b/content/docs/Cpp/hello-world/index.org
index 1e275110..b830006e 100644
--- a/content/docs/Cpp/hello-world/index.org
+++ b/content/docs/Cpp/hello-world/index.org
@@ -8,8 +8,8 @@ series:
   - C++
 tags:
   - C++
-  -Computer science
-  -Easy
+  - Computer science
+  - Easy
   - Basic knowledge
 ---