Solution.java

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {
    public ListNode removeNodes(ListNode head) {
        List<Integer> nums = new ArrayList<>();
        while (head != null) {
            nums.add(head.val);
            head = head.next;
        }
        Deque<Integer> stk = new ArrayDeque<>();
        for (int v : nums) {
            while (!stk.isEmpty() && stk.peekLast() < v) {
                stk.pollLast();
            }
            stk.offerLast(v);
        }
        ListNode dummy = new ListNode();
        head = dummy;
        while (!stk.isEmpty()) {
            head.next = new ListNode(stk.pollFirst());
            head = head.next;
        }
        return dummy.next;
    }
}