public int delete(int data){
		
		Link lk=findLink(data);
		
		if(lk.prior!=null)
			lk.prior.next=lk.next;
		else
			first=lk.next;
		
		if(lk.next!=null)
			lk.next.prior=lk.prior;
		else
			last=lk.prior;
		
		return lk.data;
		
	}