循环有序列表的插入

/*
 * 问题思路：
 * 1. 将链表转换为ArrayList。
 * 2. 使用Stream API找到合适的插入点。
 * 3. 插入新值并将ArrayList转回循环链表。
 */
import java.util.ArrayList;
import java.util.stream.IntStream;

public class SolutionStream {
    static class Node {
        public int val;
        public Node next;
        public Node() {}
        public Node(int _val) {
            val = _val;
        }
        public Node(int _val, Node _next) {
            val = _val;
            next = _next;
        }
    }

    public Node insert(Node head, int insertVal) {
        if (head == null) {
            Node newNode = new Node(insertVal);
            newNode.next = newNode;
            return newNode;
        }

        ArrayList<Node> nodes = new ArrayList<>();
        Node current = head;
        do {
            nodes.add(current);
            current = current.next;
        } while (current != head);

        int size = nodes.size();
        int insertIndex = IntStream.range(0, size)
            .filter(i -> (nodes.get(i).val <= insertVal && insertVal <= nodes.get((i + 1) % size).val)
                    || (nodes.get(i).val > nodes.get((i + 1) % size).val &&
                        (insertVal >= nodes.get(i).val || insertVal <= nodes.get((i + 1) % size).val)))
            .findFirst()
            .orElse(size - 1);

        Node newNode = new Node(insertVal, nodes.get((insertIndex + 1) % size));
        nodes.get(insertIndex).next = newNode;
        return head;
    }
}