diff --git a/googletest/samples/sample2.cc b/googletest/samples/sample2.cc
index f3b722f..d8e8723 100644
--- a/googletest/samples/sample2.cc
+++ b/googletest/samples/sample2.cc
@@ -35,7 +35,7 @@
 
 // Clones a 0-terminated C string, allocating memory using new.
 const char* MyString::CloneCString(const char* a_c_string) {
-  if (a_c_string == NULL) return NULL;
+  if (a_c_string == nullptr) return nullptr;
 
   const size_t len = strlen(a_c_string);
   char* const clone = new char[ len + 1 ];