#include <iostream>

using namespace std;

class List
{
private:
    struct Node
    {
        int value;
        Node* prev;
        Node* next;
    };
    Node* first;
    Node* last;
    int indicator;

public:
    List()
    {
        first = NULL;
        last = NULL;
        indicator = 0;
    }


    void OneShot(int v)
     {
         Node* temp = new Node;
         temp->value = v;
         cout << temp->value <<'\n';
         temp->prev = last;

         if ( (temp->value < 0)&(indicator == 0) )
         {
             delete temp;
             ++indicator;
         }
         else
         {
             if(last)
             {
                 last->next = temp;
                 last = temp;
                 temp->next = NULL;
             }
             else
             {
                 first = temp;
                 temp->next = NULL;
                 last = temp;
             }
         }
     }

   void print()
    {
        Node* temp = first;
        while( temp != NULL )
        {
            cout << temp->value << '\n';
            temp = temp->next;
        }
    }

    ~List()
    {
        Node* temp = first;
        while (first != NULL)
        {
            temp = first;
            first = first->next;
            delete temp;
        }
    }
};

int main()
{
    List l;
    cout << "List:"<<'\n';
    l.OneShot(1);
    l.OneShot(2);
    l.OneShot(-3);
    l.OneShot(4);
    l.OneShot(-5);
    l.OneShot(6);
    cout << "New List:"<<'\n';
    l.print();
   return 0;
}