diff --git a/lesson_6/exercise_1.hpp b/lesson_6/exercise_1.hpp
index ad56841..cb97401 100644
--- a/lesson_6/exercise_1.hpp
+++ b/lesson_6/exercise_1.hpp
@@ -16,9 +16,9 @@ static std::mutex mtx_cout;
 class pcout
 {
 private:
-    std::lock_guard<std::mutex> lk;
+    std::lock_guard<std::mutex> lg;
 public:
-    pcout() : lk(std::lock_guard<std::mutex>(mtx_cout))
+    pcout() : lg(std::lock_guard<std::mutex>(mtx_cout))
     {
     }