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42 lines
1.9 KiB
HTML
42 lines
1.9 KiB
HTML
<p>You are given a string <code>s</code> consisting only of lowercase English letters.</p>
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<p>In one <strong>move</strong>, you can select any two <strong>adjacent</strong> characters of <code>s</code> and swap them.</p>
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<p>Return <em>the <strong>minimum number of moves</strong> needed to make</em> <code>s</code> <em>a palindrome</em>.</p>
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<p><strong>Note</strong> that the input will be generated such that <code>s</code> can always be converted to a palindrome.</p>
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<p> </p>
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<p><strong>Example 1:</strong></p>
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<pre>
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<strong>Input:</strong> s = "aabb"
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<strong>Output:</strong> 2
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<strong>Explanation:</strong>
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We can obtain two palindromes from s, "abba" and "baab".
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- We can obtain "abba" from s in 2 moves: "a<u><strong>ab</strong></u>b" -> "ab<u><strong>ab</strong></u>" -> "abba".
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- We can obtain "baab" from s in 2 moves: "a<u><strong>ab</strong></u>b" -> "<u><strong>ab</strong></u>ab" -> "baab".
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Thus, the minimum number of moves needed to make s a palindrome is 2.
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</pre>
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<p><strong>Example 2:</strong></p>
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<pre>
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<strong>Input:</strong> s = "letelt"
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<strong>Output:</strong> 2
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<strong>Explanation:</strong>
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One of the palindromes we can obtain from s in 2 moves is "lettel".
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One of the ways we can obtain it is "lete<u><strong>lt</strong></u>" -> "let<u><strong>et</strong></u>l" -> "lettel".
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Other palindromes such as "tleelt" can also be obtained in 2 moves.
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It can be shown that it is not possible to obtain a palindrome in less than 2 moves.
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</pre>
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<p> </p>
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<p><strong>Constraints:</strong></p>
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<ul>
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<li><code>1 <= s.length <= 2000</code></li>
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<li><code>s</code> consists only of lowercase English letters.</li>
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<li><code>s</code> can be converted to a palindrome using a finite number of moves.</li>
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</ul>
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