求教一个js简易问题

Question

<p title="a gentle reminder">don't forget to buy this stuff.</p><ul id="purchases">    <li title="one">a tin of beans</li>    <li class="sale" title="two">cheese</li>    <li class="sale important">milk</li></ul><script>    var shopping = document.getElementsById("purchases");    var items = shopping.getElementsByTagName("*");    alert (items.length);</script>

Answer 1

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