//full function

class Solution

{

    public:

    //Function to delete a node at given position.

    Node* deleteNode(struct Node *head_ref,int x)

    {

        //initializing del node with head_ref.

        struct Node *del = head_ref;

        x = x-1;

        //iterating till the position given in parameter.

        while(x--)

            del = del->next;

        /* base case */

        //if head_ref or del is null, return null.

        if(head_ref == NULL || del == NULL)

            return NULL;

        /* If Node to be deleted is head Node */

        //if del is equal to head_ref, update head_ref to next node.

        if(head_ref == del)

            head_ref = del->next;

        /* Change next only if Node to be deleted is NOT the last Node */

        //if del next is not null, update previous node of del next to del previous.

        if(del->next != NULL)

            del->next->prev = del->prev;

        /* Change prev only if Node to be deleted is NOT the first Node */

        //if del previous is not null, update next node of del previous to del next.

        if(del->prev != NULL)

            del->prev->next = del->next;

        /* Finally, free the memory occupied by del*/

        //free up the memory of del node.

        free(del);

        //return updated head_ref.

        return head_ref;

    }     

};