#include #include #include /* >>>>>> SET THE FONT SIZE TO SMALL!! <<<<<< What is Smart Pointer? It's a type whose values can be used like pointers, but which provides the addtional feature of automatic memory management. Example if you are calling new, you will need to delete it. If you forgot to delete it (freed the memory), it will cause a memory leaks. But with smart pointer, If you are calling new. You don't have to call delete because it will be automatically deleted when goes out of the scope. Tips : - If you do not plan on sharing the resource between multiple threads, use a unique_ptr. - If you use a shared_ptr and you didn't share it, it will cause Unnecessary Resource Utilization and might cause Subtle Bugs. - Use make_shared to instantiate shared pointers instead of using the raw pointer. P.S Don't forgot to include if you want to use Smart Pointer and i'm very highly recommend you to use Debugger, so you will know how the code runs. */ struct Student { std::string name; Student(std::string name) : name(name) { std::cout << name << " Constructed!\n"; } ~Student() { std::cout << name << " Destructed!\n"; } void GetStudy() { std::cout << name << " get study for the bright future..\n"; } }; int main() { // case 1 // // student01 will be get deleted after it goes out of scope even we didn't call delete { std::unique_ptr student01 = std::make_unique("Jimmy"); student01->GetStudy(); } // case 2 // // if you copy unique pointer, it will be failed because unique pointer can't be copied { std::unique_ptr student02 = std::make_unique("Hendry"); //std::unique_ptr student03 = student02; // Fails.. } // case 3 // // if you want to copy smart pointer, you might want to use shared pointer /* How it works? Smart pointer allocates a small block of memory to contain the reference counter. Each copy of the Smart pointer receives a pointer to reference count. So it will be deleted, when the reference counter reach to zero. */ { std::shared_ptr student04 = std::make_shared("Axel"); { // succeeded std::shared_ptr student05 = student04; // check the existence (Helper) student05->GetStudy(); /* After student05 goes out of this scope, student05 will be remaining (Or not deleted) until reference counter reach to zero */ } // check the existence (Helper) student04->GetStudy(); /* After student04 goes out of this scope, those smart pointer will be deleted (freed the memory) because reference counter reach to zero */ } // case 4 // // weak pointer its like shared pointer but it doesn't increase the reference counter { std::weak_ptr student06; { std::shared_ptr student07 = std::make_shared("Vecroz"); student06 = student07; /* After student07 goes out of this scope, those smart pointer will be deleted (freed the memory) because reference counter reach to zero */ } } return 0; }