Finish Ch. 1

ch_1/initialization/main.cpp

@@ -5,7 +5,11 @@ int main() {
     double pi { 3.1415 };
     [[maybe_unused]] double tau { 6.2830 };
 
-    std::cout << pi;
+    std::cout << pi << std::endl;
+
+    int y;
+
+    std::cout << "y is uninitialized. it's value is " << y << "\n";
 
     return 0;
 }