DELETE A NODE FROM A SIMPLE DOUBLY LINKED LIST...

// DELETE A NODE FROM A SIMPLE DOUBLY LINKED LIST


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

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

      class D_link
     {
       private: int num ;
            Double start;

       public:
           void Doubly_Link_Del (Double *);
           void Doubly_Link_Creat (Double *);
           void display (Double *);
    };

// Function creates a doubly linked list

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

       num = 0;

      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 values of the node :"<<(num+1)<< " : ";
       cin >> node->info;
        node->next = NULL;

         cout<<"\n Input choice n for break:";
          ch = getche();
           num ++;
       }
       cout<<"\n Total nodes = "<<num;
     }

////////////////////////////////////////////////////
// Function delete

  void D_link :: Doubly_Link_Del (Double *node)
      {
       int delete_node;
       int search_counter = 0;

       cout<<"\n Input the node number to which you want delete: ";
       cin >> delete_node;

       node = start.next;
       if ( node == NULL)
        {
          cout<<"\n Underflow\n";
          cout<<"\n List is empty\n";
        }
       else

     while(node)
       {
     if((search_counter + 1) == delete_node)
        {
          node->previous->next = node->next ;
          node->next->previous = node->previous ;
          free(node);
         }
       else
        {
         node = node->next;

        }
         search_counter++;
       }
     }

////////////////////////////////////////////////////
    // Display the list

   void D_link :: display(Double *node)
     {
      node = start.next;

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

// Function main

    void main()
     {
       D_link Doubly_del;
        Double *node = (Double *) malloc(sizeof(Double));
         Doubly_del.Doubly_Link_Creat(node);
          cout<<"\n Created linked list is as follows\n";
           Doubly_del.display(node);
          Doubly_del.Doubly_Link_Del(node);
        cout<<"\n After deletion of a node linked list is as follows\n";
      Doubly_del.display(node);
     }