剑指Offer LeetCode　面试题22. 链表中倒数第k个节点

package 链表;

public class Solution {
    public static  ListNode getKthFromEnd(ListNode head, int k) {

        ListNode a = head,b=head;

        for (int i = 0; i < k ; i++) {
            b = b.next;
        }

        while (b!=null){
            a=a.next;
            b=b.next;
        }

        return a;
    }

    public static void main(String[] args) {
        ListNode l1 = new ListNode(1);
        ListNode l2 = new ListNode(3);
        ListNode l3 = new ListNode(2);
        //https://leetcode-cn.com/problems/shan-chu-lian-biao-de-jie-dian-lcof/
        l1.next=l2;
        l2.next=l3;

        ListNode listNode = getKthFromEnd(l1, 2);
        while (listNode!=null){
            System.out.println(listNode.val);
            listNode=listNode.next;
        }
    }
}

class ListNode {

    int val;
    ListNode next;
    ListNode(int x) { val = x; }

}