�PNG  IHDR��;���IDATx��ܻn�0���K�� �)(�pA��� ���7�LeG{�� �§㻢|��ذaÆ 6lذaÆ 6lذaÆ 6lom��$^�y���ذag�5bÆ 6lذaÆ 6lذa{���� 6lذaÆ �`����}H�Fkm�,�m����Ӫ���ô�ô!� �x�|'ܢ˟;�E:���9�&ᶒ�}�{�v]�n&�6� �h��_��t�ڠ͵-ҫ���Z;��Z$�.�P���k�ž)�!��o���>}l�eQfJ�T��u і���چ��\��X=8��Rن4`Vw�l�>����n�G�^��i�s��"ms�$�u��i��?w�bs[m�6�K4���O���.�4��%����/����b�C%��t ��M�ז� �-l�G6�mrz2���s�%�9��s@���-�k�9�=���)������k�B5����\��+͂�Zsٲ ��Rn��~G���R���C����� �wIcI��n7jJ���hۛNCS|���j0��8y�iHKֶۛ�k�Ɉ+;Sz������L/��F�*\��Ԕ�#"5��m�2��[S��������=�g��n�a�P�e�ғ�L�� lذaÆ 6l�^k��̱aÆ 6lذaÆ 6lذa;���� �_��ذaÆ 6lذaÆ 6lذaÆ ���R���IEND�B` function Queue () { this.head = new Item('head', null) } module.exports = Queue Queue.prototype.append = function append (kind, value) { var item = new Item(kind, value) this.head.prepend(item) return item } Queue.prototype.isEmpty = function isEmpty () { return this.head.prev === this.head } Queue.prototype.first = function first () { return this.head.next } function Item (kind, value) { this.prev = this this.next = this this.kind = kind this.value = value } Item.prototype.prepend = function prepend (other) { other.prev = this.prev other.next = this other.prev.next = other other.next.prev = other } Item.prototype.dequeue = function dequeue () { var prev = this.prev var next = this.next prev.next = next next.prev = prev this.prev = this this.next = this return this.value } Item.prototype.isEmpty = function isEmpty () { return this.prev === this }