function Clone(pHead) {
      if (pHead === null) {
        return null;
      }
      cloneNodes(pHead);
      cloneRandom(pHead);
      return reconnetNodes(pHead);
    }

    function cloneNodes(pHead) {
      var current = pHead;
      while (current) {
        var cloneNode = {
          label: current.label,
          next: current.next
        };
        current.next = cloneNode;
        current = cloneNode.next;
      }
    }

    function cloneRandom(pHead) {
      var current = pHead;
      while (current) {
        var cloneNode = current.next;
        if (current.random) {
          cloneNode.random = current.random.next;
        } else {
          cloneNode.random = null;
        }
        current = cloneNode.next;
      }
    }

    function reconnetNodes(pHead) {
      var cloneHead = pHead.next;
      var cloneNode = pHead.next;
      var current = pHead;
      while (current) {
        current.next = cloneNode.next;
        current = cloneNode.next;
        if (current) {
          cloneNode.next = current.next;
          cloneNode = current.next;
        } else {
          cloneNode.next = null;
        }
      }
      return cloneHead;
    }