manages memory and remove erros

DoublyLinkedList/DLL_operations.cpp(C++)

@@ -1,212 +0,0 @@
-#include<iostream>
-using namespace std;
-struct node{
-int info;
-struct node *next;
-struct node *prev;
-}*start;
-
-class dll
-{
-public:
-    void create_list(int value);
-    void add_begin(int value);
-    void add_after(int value, int position);
-    void delete_element(int value);
-    void display();
-    dll()
-    {
-        start=NULL;
-    }
-};
-
-int main()
-{
-    int choice, element, position;
-    dll dl;
-    while(1)
-    {
-        cout<<endl<<"--------------------------------";
-        cout<<endl<<"Operations on Doubly Linked List";
-        cout<<endl<<"--------------------------------";
-        cout<<endl<<"1-Create Node";
-        cout<<endl<<"2-Add at Beginning";
-        cout<<endl<<"3-Add after Position";
-        cout<<endl<<"4-Delete";
-        cout<<endl<<"5-Display";
-        cout<<endl<<"6-Exit";
-        cout<<endl<<"Enter Choice:";
-        cin>>choice;
-        switch(choice)
-        {
-            case 1: cout<<"Enter the element: ";
-                    cin>>element;
-                    dl.create_list(element);
-                    break;
-            case 2: cout<<"Enter the element: ";
-                    cin>>element;
-                    dl.add_begin(element);
-                    break;
-            case 3: cout<<"Enter the element: ";
-                    cin>>element;
-                    cout<<"Insert element after position: ";
-                    cin>>position;
-                    dl.add_after(element,position);
-                    break;
-            case 4: if(start==NULL)
-                    {
-                        cout<<"List empty, Nothing to delete"<<endl;
-                        break;
-                    }
-                    cout<<"Enter element for deletion: ";
-                    cin>>element;
-                    dl.delete_element(element);
-                    break;
-            case 5: dl.display();
-                    break;
-            case 6: exit(1);
-            default: cout<<"Wrong Choice"<<endl;
-        }
-    }
-    return 0;
-}
-
-
-void dll::create_list(int value)
-{
-    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 dll::add_begin(int value)
-{
-    if(start==NULL)
-    {
-        cout<<"First create the list"<<endl;
-        return;
-    }
-    struct node *temp;
-    temp=new(struct node);
-    temp->prev=NULL;
-    temp->info=value;
-    temp->next=start;
-    start->prev=temp;
-    start=temp;
-    cout<<"Element inserted"<<endl;
-}
-
-
-void dll::add_after(int value, int pos)
-{
-    if(start=NULL)
-    {
-        cout<<"first create the list"<<endl;
-        return;
-    }
-    struct node *temp, *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;
-        }
-    }
-    temp=new(struct node);
-    temp->info=value;
-    if(q->next==NULL)
-    {
-        q->next=temp;
-        temp->next=NULL;
-        temp->prev=q;
-    }
-    else
-    {
-        temp->next=q->next;
-        temp->next->prev=temp;
-        q->next=temp;
-        temp->prev=q;
-    }
-    cout<<"Element inserted"<<endl;
-}
-
-
-void dll::delete_element(int value)
-{
-    struct node *temp, *q;
-    /*first element deletion*/
-    if(start->info==value)
-    {
-        temp=start;
-        start=start->next;
-        start->prev=NULL;
-        cout<<"Element deleted"<<endl;
-        free(temp);
-        return;
-    }
-    q=start;
-    while(q->next->next != NULL)
-    {
-        /*element deleted in between*/
-        if(q->next->info==value)
-        {
-            temp=q->next;
-            q->next=temp->next;
-            temp->next->prev=q;
-            cout<<"Element deleted"<<endl;
-            free(temp);
-            return;
-        }
-        q=q->next;
-    }
-    /*Last element deleted*/
-    if(q->next->info==value)
-    {
-        temp=q->next;
-        free(temp);
-        q->next=NULL;
-        cout<<"Element deleted"<<endl;
-        return;
-    }
-    cout<<"Element "<<value<<" not found"<<endl;
-}
-
-
-void dll::display()
-{
-    struct node *q;
-    if(start==NULL)
-    {
-        cout<<"List empty,Nothing to display"<<endl;
-        return;
-    }
-    q=start;
-    cout<<"The doubly linked list is: "<<endl;
-    while(q!=NULL)
-    {
-        cout<<q->info<<"->";
-        q=q->next;
-    }
-    cout<<"NULL"<<endl;
-}