<p>Given the <code>head</code> of a singly linked list where elements are sorted in <strong>ascending order</strong>, convert <em>it to a </em><span data-keyword="height-balanced"><strong><em>height-balanced</em></strong></span> <em>binary search tree</em>.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://assets.leetcode.com/uploads/2020/08/17/linked.jpg" style="width: 500px; height: 388px;" /> <pre> <strong>Input:</strong> head = [-10,-3,0,5,9] <strong>Output:</strong> [0,-3,9,-10,null,5] <strong>Explanation:</strong> One possible answer is [0,-3,9,-10,null,5], which represents the shown height balanced BST. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> head = [] <strong>Output:</strong> [] </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in <code>head</code> is in the range <code>[0, 2 * 10<sup>4</sup>]</code>.</li> <li><code>-10<sup>5</sup> <= Node.val <= 10<sup>5</sup></code></li> </ul>