public void insertBefore(int data){
		Link lk=new Link();
		lk.data=data;
		
		if(current.prior!=null){
			current.prior.next=lk;
			lk.prior=current.prior;
		}
		else
			mylist.first=lk;
		lk.next=current;
		current.prior=lk;		
		
	}