MERGING TWO DOUBLY LINKED LISTS (ASCENDING ORDER)....

//  MERGING TWO DOUBLY LINKED LISTS (ASCENDING ORDER)


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

    struct Double
    {
     int info;
     struct Double *next;
     struct Double *previous;
   };

  class D_insert
    {
       public:  int i;
            Double  start, start1, *new1, *local;
       public:
            void Doubly_insertion (Double * );
            void Doubly_Create (Double * );
            void Display (Double *);
    };

// Function create a list of five nodes

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


    for (i = 1; i < 10; i += 2)
         {
           node->next = (Double *) malloc(sizeof(Double ));
           node->next->previous = node;
           node = node->next;
           node->info = i;
           node->next = NULL;
         }
    }


 void D_insert :: Doubly_insertion (Double *node)
   {
       Double *new1;
       start1.next = NULL;  // Empty list
       start1.previous = NULL;
       new1 = &start1;      // Point to the start of the list

    for (i = 2; i <= 10; i += 2)
         {
           new1->next = (Double *) malloc(sizeof(Double ));
           new1->next->previous = new1;
           new1= new1->next;
           new1->info = i;
           new1->next = NULL;
         }

    new1 = start1.next;
    cout<<"\n Second list is as follows";
    while(new1)
    {
      cout<<"\n "<<new1;
      cout<<"  "<<new1->info;
      new1 = new1->next;
    }
    new1 = start1.next;

     while(new1)
     {
       int found = 0;
       local = (Double *) malloc(sizeof(Double));
       local = new1;
       new1 = new1->next;

       node = start.next;

       do
    {
     if ( node->info > local->info )
       {
         local->next = node;
         local->previous = node->previous;
         node->previous->next = local;
         node->previous = local;
         found = 1;
         break;
         }
     else
       node = node->next;
       } while ((node->next) && (! found));

       if (! found)
    if (node->info> local->info)
      {
         local->next = node;
         local->previous = node->previous;
         node->previous->next = local;
         node->previous = local;
      }
       else
      {
         local->next = NULL;
         local->previous = node;
         node->next = local;

      }
     }
   }

 // 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 (node);
      cout<<"\n First list is as follows\n";
      D_ins.Display (node);
      D_ins.Doubly_insertion (node);
      cout<<"\n List after merging above two lists (Ascending order)\n";
      D_ins.Display (node);

    }