Merge branch 'master' of https://github.com/Evil2017/C-Primer5

Author: Evil2017

ch01/ex1_09.cpp

@@ -11,6 +11,7 @@ int main()
     }
     std::cout << "the sum is: " << sum << std::endl;
     system("pause");
+    system("pause");
     return 0;
 }