I have done a bare bones implementation of a Singly Linked List in C++, which works. Here’s my node class

template <typename T> class ListNode{     template <typename U > friend class SinglyLinkedList; private:     T data_;     ListNode<T>* next_; public:     ListNode(void):             data_{0},             next_{nullptr}{}     ListNode(T data_):             data_{data_},             next_{nullptr} {}  }; 

Here’s the list class,

template <typename T> class SinglyLinkedList{ private:     ListNode<T>* head_;     std::size_t size_; public:     SinglyLinkedList():             head_{nullptr},             size_{0}{}      void insert(T item){         ListNode<T> * p{new ListNode<T>(item)};         if (size_ == 0){             head_ = p;         }else{             p->next_ = head_;             head_ = p;         }         size_++;     }     std::size_t getSize(){         return size_;     }  }; 

Here’s what I’m looking to learn and understand,

1. A review.

2. Where is the new’ed up Node in the insert deleted(released)?

3. Is there a way to implement this without new at all?

4. Is there a difference between the following lines?

   ListNode(void): data_{0}, next_{nullptr}{}

and ListNode(void): data_(0), next_(nullptr){}