<p>You are given a string <code>s</code> containing lowercase letters and an integer <code>k</code>. You need to :</p> <ul> <li>First, change some characters of <code>s</code> to other lowercase English letters.</li> <li>Then divide <code>s</code> into <code>k</code> non-empty disjoint substrings such that each substring is a palindrome.</li> </ul> <p>Return <em>the minimal number of characters that you need to change to divide the string</em>.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> s = "abc", k = 2 <strong>Output:</strong> 1 <strong>Explanation:</strong> You can split the string into "ab" and "c", and change 1 character in "ab" to make it palindrome. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> s = "aabbc", k = 3 <strong>Output:</strong> 0 <strong>Explanation:</strong> You can split the string into "aa", "bb" and "c", all of them are palindrome.</pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> s = "leetcode", k = 8 <strong>Output:</strong> 0 </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= k <= s.length <= 100</code>.</li> <li><code>s</code> only contains lowercase English letters.</li> </ul>