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import { Node } from "./Node.ts";
const cachedNode = new WeakMap<Node, Node>();export default function copyRandomList(head: Node | null): Node | null {    if (head === null) {        return null;    }    if (!cachedNode.has(head)) {        const cloned = new Node();        cachedNode.set(head, cloned);
        cloned.val = head.val;        cloned.next = copyRandomList(head.next);        cloned.random = copyRandomList(head.random);        return cloned;    }    const result = cachedNode.get(head);    return result ? result : null;}