NEW AIR

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include <vector>
using namespace std;

    struct node

    {

        int info;

        struct node *next;

        struct node *prev;

    }*start,*last;



    /*

     Class Declaration

     */

    class double_llist

    {

        public:

            void create_list(int value);

            void add_after(int value, int position);

            void delete_element_first(int value);
            void delete_element_last();

            int search_element(int value);

            void display_dlist();


            double_llist()

            {

                start = NULL;
                last= NULL;

            }

    };



    /*

     * Main: Conatins Menu

     */

    int main()

    {
        struct node *q = start;

        int choice, element, position;

        double_llist dl;

        while (1)

        {
 //خيارات ستفيد منها المستخدم لمعرفة ايلامور التي يجب ان يفعلها
            cout<<endl<<"----------------------------"<<endl;

            cout<<endl<<"Operations on Doubly linked list"<<endl;

            cout<<endl<<"----------------------------"<<endl;

            cout<<"1.Create Node"<<endl;


            cout<<"2.Add after position"<<endl;

            cout<<"3.Delete first "<<endl;
               cout<<"4.Delete last "<<endl;
               cout<<"5.search element"<<endl;

            cout<<"6.Display"<<endl;



            cout<<"7.Quit"<<endl;





            cout<<"Enter your choice : ";

            cin>>choice;

            switch ( choice )

            {

            case 1:

                cout<<"Enter the element: ";

                cin>>element;

                dl.create_list(element);

                cout<<endl;

                break;



            case 2:

                cout<<"Enter the element: ";

                cin>>element;

                cout<<"Insert Element after postion: ";

                cin>>position;

                dl.add_after(element, position);

                cout<<endl;

                break;

            case 3:

                if (start == NULL)

                {

                    cout<<"List empty,nothing to delete"<<endl;

                    break;

                }


                dl.delete_element_first(start->info);

                cout<<endl;

                break;
                case 4 :
                if (start == NULL)

                {

                    cout<<"List empty,nothing to delete"<<endl;

                    break;

                }


                dl.delete_element_last();

                cout<<endl;
                break;

              case 5:
                int value;
                cout<<"Enter the value please";
                cin>>value;
                cout<<dl.search_element(value)<<endl;;
            break;

            case 6:

                dl.display_dlist();

                cout<<endl;

                break;




            case 7:

                exit(1);

            default:

                cout<<"Wrong choice"<<endl;

            }

        }

        return 0;

    }



    /*

     * Create Double Link List

     */

    void double_llist::create_list(int value)// تابع لإنشاء السجل

    {

        struct node *s, *temp;

        temp = new(struct node);

        temp->info = value;

        temp->next = NULL;

        if (start == NULL)

        {

            temp->prev = NULL;

            start = temp;

        }

        else

        {

            s = start;

            while (s->next != NULL)

                s = s->next;

            s->next = temp;

            temp->prev = s;

        }

    }




    void double_llist::add_after(int value, int pos)// تابع نقوم من خلاله بإضافة قيمة إلى موقع محدد نقوم من خلاله بعمليه تأخير للعناصر التي تسبق الموقع وتقديم للعناصر التي تليه

    {

        if (start == NULL)

        {

            cout<<"First Create the list."<<endl;

            return;

        }

        struct node *tmp, *q;

        int i;

        q = start;

        for (i = 0;i < pos - 1;i++)

        {

            q = q->next;

            if (q == NULL)

            {

                cout<<"There are less than ";

                cout<<pos<<" elements."<<endl;

                return;

            }

        }

        tmp = new(struct node);

        tmp->info = value;

        if (q->next == NULL)

        {

            q->next = tmp;

            tmp->next = NULL;

            tmp->prev = q;

        }

        else

        {

            tmp->next = q->next;

            tmp->next->prev = tmp;

            q->next = tmp;

            tmp->prev = q;

        }

        cout<<"Element Inserted"<<endl;

    }



    /*

     * Deletion of element from the list

     */

    void double_llist::delete_element_first(int value)// تابع حذف العقدة الاولى

    {

        struct node *tmp, *q;

         /*first element deletion*/

        if (start->info == value)

        {

            tmp = start;

            start = start->next;

            start->prev = NULL;

            cout<<"Element Deleted"<<endl;

            free(tmp);

            return;

        }

        q = start;

        while (q->next->next != NULL)

        {

            /*Element deleted in between*/

            if (q->next->info == value)

            {

                tmp = q->next;

                q->next = tmp->next;

                tmp->next->prev = q;

                cout<<"Element Deleted"<<endl;

                free(tmp);

                return;

            }

            q = q->next;

        }

         /*last element deleted*/

        if (q->next->info == value)

        {

            tmp = q->next;

            free(tmp);

            q->next = NULL;

            cout<<"Element Deleted"<<endl;

            return;

        }

        cout<<"Element "<<value<<" not found"<<endl;

    }



    /*

     * Display elements of Doubly Link List

     */

    void double_llist::display_dlist()// تابع إظهار للعقدة كاملة

    {

        struct node *q;

        if (start == NULL)

        {

            cout<<"List empty,nothing to display"<<endl;

            return;

        }

        q = start;

        cout<<"The Doubly Link List is :"<<endl;

        while (q != NULL)

        {

            cout<<q->info<<" <-> ";

            q = q->next;

        }

        cout<<"NULL"<<endl;

    }
    void double_llist::delete_element_last() // تابع حذف القيمة الاخيرة
    {

        struct node *tmp, *q;

        tmp = start;
        vector<node*> v;
        while(tmp!=NULL)
        {
            v.push_back(tmp);
            tmp=tmp->next;
        }

        int N = v.size();
        delete v[N-1];
        v[N-1]=NULL;
        if(N>1)v[N-2]->next = NULL;
    }
    int double_llist::search_element(int value)// تابع للبحث عن قيمة معينة
{
        struct node *q = start;

    int cnt = 0;

    while (q != NULL)
    {
        if(q->info==value)return cnt;
        q = q->next;
        cnt++;
    }
    return -1;
}