<p>Given an integer <code>n</code>, return <em>the number of positive integers in the range </em><code>[1, n]</code><em> that have <strong>at least one</strong> repeated digit</em>.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> n = 20 <strong>Output:</strong> 1 <strong>Explanation:</strong> The only positive number (<= 20) with at least 1 repeated digit is 11. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> n = 100 <strong>Output:</strong> 10 <strong>Explanation:</strong> The positive numbers (<= 100) with atleast 1 repeated digit are 11, 22, 33, 44, 55, 66, 77, 88, 99, and 100. </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> n = 1000 <strong>Output:</strong> 262 </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= n <= 10<sup>9</sup></code></li> </ul>