<pre class="shiki github-dark shaku"><code>/** * @param {HTMLElement} tree * @return {string[]} */function getTags(tree) { // your code here let treeset = new Set() const getArr = (node) =&gt; { if(!node || node.nodeType !== Node.ELEMENT_NODE) return treeset.add(node.tagName.toLowerCase()) for(let child of node.children){ getArr(child) } } getArr(tree) return Array.from(treeset)}// let div = document.createElement("div")// let p = document.createElement("p")// let button = document.createElement("button")// p.textContent = "adiya"// p.appendChild(button);// div.appendChild(p)// console.log(getTags(div))</code></pre>

accepted code

Given a DOM tree, please return all the tag names it has. Your function should return a unique array of tags names in lowercase, order doesn't matter.…