static SNode mergeSortedList(SNode head1, SNode head2){
        if(head1 == null)
            return head2;
        if(head2 == null)
            return head1;
        SNode curr1 = head1;
        SNode curr2 = head2;
        SNode curr = null; 
        SNode head = null;

        while(curr1 != null || curr2 != null){
            if(curr1 == null){
                if(curr != null)
                    curr.next = new SNode(curr2.data);
                else
                    head = curr = new SNode(curr2.data);

                curr2 = curr2.next;

            }else if(curr2 == null){
                if(curr != null)
                    curr.next = new SNode(curr1.data);
                else
                    head = curr = new SNode(curr1.data);

                curr1 = curr1.next;
            }else{
                if(curr1.data < curr2.data){
                    if(curr == null){
                        head = curr = new SNode(curr1.data);
                    }else{
                        curr.next = new SNode(curr1.data);
                    }

                    curr1 = curr1.next;
                }else{
                    if(curr == null)
                        head = curr = new SNode(curr2.data);
                    else{
                        curr.next = new SNode(curr2.data);
                    }

                    curr2 = curr2.next;
                }
            }

            if(curr.next != null)
                curr = curr.next;
        }
        return head;
    }