build fixes

Lesson_9/SmartPointer/Car.h

@@ -1,6 +1,4 @@
 #pragma once
-
-
 class Car
 {
 public:

Lesson_9/SmartPointer/CarFactory.cpp

@@ -4,5 +4,5 @@
 
 std::unique_ptr<Car> CarFactory::BuildCar(const std::string& color)
 {
-        return std::make_unique<Car>(new Car(color));
+        return std::make_unique<Car>(color);
 }

Lesson_9/SmartPointer/CarFactory.h

@@ -1,5 +1,5 @@
 #pragma once
-#include "Car.h"
+class Car;
 
 class CarFactory
 {

Lesson_9/SmartPointer/Driver.cpp

@@ -9,14 +9,19 @@ Driver::Driver(const std::string& name, std::shared_ptr<CarFactory> factory)
 {
 }
 
+Driver::~Driver() 
+{
+    /*to avoid errors from incomplete type in unique_ptr*/
+}
+
 void Driver::BuyCar(const std::string& color)
 {
     car_ = factory_->BuildCar(color);
 }
 
 std::unique_ptr<Car> Driver::SellCar()
 {
-    return std::make_unique<Car>(car_.release());
+    return std::unique_ptr<Car>(car_.release());
 }
 
 void Driver::BuyUsedCar(Driver * d)

Lesson_9/SmartPointer/Driver.h

@@ -1,11 +1,12 @@
 #pragma once
-#include "Car.h"
+class Car;
 class CarFactory;
 
 class Driver
 {
 public:
     Driver(const std::string& name, std::shared_ptr<CarFactory> factory);
+    ~Driver();
 
     void BuyCar(const std::string& color);