INSERTING SOME NODES IN THE DOUBLY LINKED LIST...

//  INSERTING SOME NODES IN THE DOUBLY LINKED LIST


 # include<iostream.h>
 # include <stdio.h>
 # include <alloc.h>
 # include<conio.h>

    struct Double
    {
     char info[20];
     struct Double *next;
     struct Double *previous;
   };

  class D_insert
    {
       public:  int i;
            Double  start, *new1;
       public:
            void Doubly_insertion_First (Double *);
            void Doubly_Create_First (Double *);
            void Display (Double *);
    };

// Function create a list of five nodes

  void D_insert :: Doubly_Create_First (Double *node)
      {
       int i = 0;
    start.next = NULL;  // Empty list
     start.previous = NULL;
      node = &start;      // Point to the start of the list

    cout<<"\n Input choice n for break: ";
     char ch = getche();

       while (ch != 'n')
         {
          node->next = (Double *) malloc(sizeof(Double ));
           node->next->previous = node;
        node = node->next;
         cout<<"\n Input the value for :"<<i+1<<" : ";
           cin>>node->info;
         node->next = NULL;
       i++;
     cout<<"\n Input choice n for break: ";
    ch = getche();
     }
  }


 void D_insert :: Doubly_insertion_First (Double *node)
   {
       node = start.next;

       new1 = (Double *) malloc(sizeof(Double ));
       cout<<"\n Input the first node  value; ";
       cin>>new1->info;
         cout<<"\n new1 address:"<<new1;
         cout<<"\n Node address:"<<node;
         new1->next = node;
         cout<<"\n New1 next address:"<<new1->next;
         cout<<"\n Node previous address:"<<node->previous;
         new1->previous = node->previous;
         node->previous->next = new1;
         cout<<"\n node->previous.next:"<<node->previous->next;
          cout<<"\n Node previous address:"<<node->previous;
          cout<<"\n Node next address:"<<node->next;
         cout<<"\n new1 address:"<<new1;
         node->previous = new1;
         cout<<"\n node->previous:"<<node->previous;
   }

 // Display the list

   void D_insert :: Display (Double *node)
      {
        node = start.next;

       while (node)
    {
      cout<<"\n "<<node;
      cout<<"  " <<node->info;
      node = node->next;
    }
      }


  void main()
    {
      D_insert D_ins;
      Double *node = (Double *) malloc(sizeof(Double));
      D_ins.Doubly_Create_First (node);
      cout<<"\n Created list is as follows\n";
      D_ins.Display(node);
      D_ins.Doubly_insertion_First (node);
      cout<<"\n List after insertion of first node \n";
      D_ins.Display (node);

    }