Update grpc-common and grpc-java url
diff --git a/cpp/helloworld/README.md b/cpp/helloworld/README.md
index 952325b..16456a8 100644
--- a/cpp/helloworld/README.md
+++ b/cpp/helloworld/README.md
@@ -12,7 +12,7 @@
 
 
 ```sh
-$ git clone https://github.com/google/grpc-common.git
+$ git clone https://github.com/grpc/grpc-common.git
 ```
 
 Change your current directory to grpc-common/cpp/helloworld