public static void main(String args[]){
        LinkList ll = new LinkList();
        Node head = null;
        head = ll.addNode(1, head);
        head = ll.addNode(2, head);
        head = ll.addNode(3, head);
        head = ll.addNode(4, head);
        head = ll.addNode(5, head);
        head = ll.addNode(6, head);
        head = ll.addNode(7, head);
        head = ll.addNode(8, head);
        ReverseKNodes rn = new ReverseKNodes();
        head = rn.reverse(head, 3);
        ll.printList(head);
    }
http://www.geeksforgeeks.org/pairwise-swap-elements-of-a-given-linked-list/
Test case
odd or even number of k
odd or even number of nodes in the list
src/com/interview/linklist/ReverseKNodes.java