<p>The <strong>DNA sequence</strong> is composed of a series of nucleotides abbreviated as <code>'A'</code>, <code>'C'</code>, <code>'G'</code>, and <code>'T'</code>.</p> <ul> <li>For example, <code>"ACGAATTCCG"</code> is a <strong>DNA sequence</strong>.</li> </ul> <p>When studying <strong>DNA</strong>, it is useful to identify repeated sequences within the DNA.</p> <p>Given a string <code>s</code> that represents a <strong>DNA sequence</strong>, return all the <strong><code>10</code>-letter-long</strong> sequences (substrings) that occur more than once in a DNA molecule. You may return the answer in <strong>any order</strong>.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre><strong>Input:</strong> s = "AAAAACCCCCAAAAACCCCCCAAAAAGGGTTT" <strong>Output:</strong> ["AAAAACCCCC","CCCCCAAAAA"] </pre><p><strong class="example">Example 2:</strong></p> <pre><strong>Input:</strong> s = "AAAAAAAAAAAAA" <strong>Output:</strong> ["AAAAAAAAAA"] </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= s.length <= 10<sup>5</sup></code></li> <li><code>s[i]</code> is either <code>'A'</code>, <code>'C'</code>, <code>'G'</code>, or <code>'T'</code>.</li> </ul>