// Runtime: 29 ms, beats 84.99 % of java submissions
class Solution {
    public int[] nextLargerNodes(ListNode head) {
        Map<ListNode, Integer> map = new HashMap<>();

        ListNode c = head;
        while (c != null) c = nextMax(c, map);

        int pos = 0;
        int[] result = new int[map.size()];

        c = head;
        while (c != null) {
            result[pos++] = map.get(c);
            c = c.next;
        }

        return result;
    }

    private ListNode nextMax(ListNode from, Map<ListNode,Integer> map) {
        ListNode next = from.next;
        while (next != null) {
            if (next.val > from.val){
                map.put(from, next.val);
                return next;
            }
            next = nextMax(next, map);
        }
        map.put(from, 0);
        return null;
    }
}