<p>Given an alphanumeric string <code>s</code>, return <em>the <strong>second largest</strong> numerical digit that appears in </em><code>s</code><em>, or </em><code>-1</code><em> if it does not exist</em>.</p> <p>An <strong>alphanumeric</strong><strong> </strong>string is a string consisting of lowercase English letters and digits.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> s = "dfa12321afd" <strong>Output:</strong> 2 <strong>Explanation:</strong> The digits that appear in s are [1, 2, 3]. The second largest digit is 2. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> s = "abc1111" <strong>Output:</strong> -1 <strong>Explanation:</strong> The digits that appear in s are [1]. There is no second largest digit. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= s.length <= 500</code></li> <li><code>s</code> consists of only lowercase English letters and digits.</li> </ul>