fix cpp
diff --git a/examples/cpp/route_guide/helper.h b/examples/cpp/route_guide/helper.h
index 65c93c1..db36596 100644
--- a/examples/cpp/route_guide/helper.h
+++ b/examples/cpp/route_guide/helper.h
@@ -37,14 +37,14 @@
#include <string>
#include <vector>
-namespace examples {
+namespace routeguide {
class Feature;
std::string GetDbFileContent(int argc, char** argv);
void ParseDb(const std::string& db, std::vector<Feature>* feature_list);
-} // namespace examples
+} // namespace routeguide
#endif // GRPC_COMMON_CPP_ROUTE_GUIDE_HELPER_H_