CC2.2.java

/*2.2 Implement an algorithm to find the kth to last element of a singly linked list.*/

public class Solution {
    public int findKth(ListNode head) {
        ListNode kth = head;
        ListNode end = head;
        int i=0;
        while(i<k) {
            end = end.next;
        }
        while(end!=null) {
            end = end.next;
            kth = kth.next;
        }
        return kth.val;
    }
}

/* the 'Remove Nth Node From End of List' on leetcode

public class Solution {
    public ListNode removeNthFromEnd(ListNode head, int n) {
        ListNode p = head;
        ListNode q = head;
        int i=0;
        while(i<n){
            q = q.next;
            i++;
        }
        if(q==null){
            head = head.next;
        } else {
            while(q.next!=null){
                p = p.next;
                q = q.next;
            }
            p.next = p.next.next;
        }
        return head;
    }
}
*/