{ "data": { "question": { "questionId": "2879", "questionFrontendId": "2911", "categoryTitle": "Algorithms", "boundTopicId": 2490371, "title": "Minimum Changes to Make K Semi-palindromes", "titleSlug": "minimum-changes-to-make-k-semi-palindromes", "content": "

Given a string s and an integer k, partition s into k substrings such that the sum of the number of letter changes required to turn each substring into a semi-palindrome is minimized.

\n\n

Return an integer denoting the minimum number of letter changes required.

\n\n

Notes

\n\n\n\n

 

\n

Example 1:

\n\n
\nInput: s = "abcac", k = 2\nOutput: 1\nExplanation: We can divide s into substrings "ab" and "cac". The string "cac" is already a semi-palindrome. If we change "ab" to "aa", it becomes a semi-palindrome with d = 1.\nIt can be shown that there is no way to divide the string "abcac" into two semi-palindrome substrings. Therefore, the answer would be at least 1.
\n\n

Example 2:

\n\n
\nInput: s = "abcdef", k = 2\nOutput: 2\nExplanation: We can divide it into substrings "abc" and "def". Each of the substrings "abc" and "def" requires one change to become a semi-palindrome, so we need 2 changes in total to make all substrings semi-palindrome.\nIt can be shown that we cannot divide the given string into two substrings in a way that it would require less than 2 changes.
\n\n

Example 3:

\n\n
\nInput: s = "aabbaa", k = 3\nOutput: 0\nExplanation: We can divide it into substrings "aa", "bb" and "aa".\nThe strings "aa" and "bb" are already semi-palindromes. Thus, the answer is zero.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "得到 K 个半回文串的最少修改次数", "translatedContent": "

给你一个字符串 s 和一个整数 k ，请你将 s 分成 k 个 子字符串 ，使得每个 子字符串 变成 半回文串 需要修改的字符数目最少。

\n\n

请你返回一个整数，表示需要修改的 最少 字符数目。

\n\n

注意：

\n\n\n\n

 

\n\n

示例 1：

\n\n
\n输入：s = \"abcac\", k = 2\n输出：1\n解释：我们可以将 s 分成子字符串 \"ab\" 和 \"cac\" 。子字符串 \"cac\" 已经是半回文串。如果我们将 \"ab\" 变成 \"aa\" ，它也会变成一个 d = 1 的半回文串。\n该方案是将 s 分成 2 个子字符串的前提下，得到 2 个半回文子字符串需要的最少修改次数。所以答案为 1 。
\n\n

示例 2:

\n\n
\n输入：s = \"abcdef\", k = 2\n输出：2\n解释：我们可以将 s 分成子字符串 \"abc\" 和 \"def\" 。子字符串 \"abc\" 和 \"def\" 都需要修改一个字符得到半回文串，所以我们总共需要 2 次字符修改使所有子字符串变成半回文串。\n该方案是将 s 分成 2 个子字符串的前提下，得到 2 个半回文子字符串需要的最少修改次数。所以答案为 2 。
\n\n

示例 3：

\n\n
\n输入：s = \"aabbaa\", k = 3\n输出：0\n解释：我们可以将 s 分成子字符串 \"aa\" ，\"bb\" 和 \"aa\" 。\n字符串 \"aa\" 和 \"bb\" 都已经是半回文串了。所以答案为 0 。\n
\n\n

 

\n\n

提示：

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