数据结构-链表中倒数最后k个结点-java

输入一个长度为 n 的链表，设链表中的元素的值为 ai ，返回该链表中倒数第k个节点。如果该链表长度小于k，请返回一个长度为 0 的链表。

public class Test {


      public static class ListNode {
        int val;
        ListNode next = null;
        public ListNode(int val) {
          this.val = val;
        }
      }

    public static ListNode FindKthToTail(ListNode pHead, int k) {
        // write code here
        Stack stack = new Stack<>();
        int t = 0;
        while(pHead!=null){
            stack.push(pHead);
            pHead = pHead.next;
            t +=1;
        }
        if (k>t){
            return null;
        }
        ListNode node = stack.pop();

        for (int i = 0; i < k-1; i++) {
            ListNode node1 = stack.pop();
            node1.next = node;
            node = node1;
            System.out.println(node.val);
            if (i==k-2){
                return node;
            }
        }
       return null;
    }

    public static void main(String[] args) {
        ListNode n1 = new ListNode(1);
        ListNode n2 = new ListNode(2);
        ListNode n3 = new ListNode(3);
        ListNode n4 = new ListNode(4);
        ListNode n5 = new ListNode(5);
        n1.next = n2;
        n2.next = n3;
        n3.next = n4;
        n4.next = n5;
        FindKthToTail(n1,2);
    }

}