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51 lines
2.0 KiB
HTML
51 lines
2.0 KiB
HTML
<p>You are given a string <code>s</code> consisting of uppercase English letters.</p>
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<p>You are allowed to insert <strong>at most one</strong> uppercase English letter at <strong>any</strong> position (including the beginning or end) of the string.</p>
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<p>Return the <strong>maximum</strong> number of <code>"LCT"</code> <span data-keyword="subsequence-string-nonempty">subsequences</span> that can be formed in the resulting string after <strong>at most one insertion</strong>.</p>
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<p> </p>
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<p><strong class="example">Example 1:</strong></p>
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<div class="example-block">
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<p><strong>Input:</strong> <span class="example-io">s = "LMCT"</span></p>
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<p><strong>Output:</strong> <span class="example-io">2</span></p>
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<p><strong>Explanation:</strong></p>
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<p>We can insert a <code>"L"</code> at the beginning of the string s to make <code>"LLMCT"</code>, which has 2 subsequences, at indices [0, 3, 4] and [1, 3, 4].</p>
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</div>
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<p><strong class="example">Example 2:</strong></p>
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<div class="example-block">
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<p><strong>Input:</strong> <span class="example-io">s = "LCCT"</span></p>
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<p><strong>Output:</strong> <span class="example-io">4</span></p>
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<p><strong>Explanation:</strong></p>
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<p>We can insert a <code>"L"</code> at the beginning of the string s to make <code>"LLCCT"</code>, which has 4 subsequences, at indices [0, 2, 4], [0, 3, 4], [1, 2, 4] and [1, 3, 4].</p>
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</div>
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<p><strong class="example">Example 3:</strong></p>
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<div class="example-block">
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<p><strong>Input:</strong> <span class="example-io">s = "L"</span></p>
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<p><strong>Output:</strong> <span class="example-io">0</span></p>
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<p><strong>Explanation:</strong></p>
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<p>Since it is not possible to obtain the subsequence <code>"LCT"</code> by inserting a single letter, the result is 0.</p>
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</div>
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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 <= 10<sup>5</sup></code></li>
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<li><code>s</code> consists of uppercase English letters.</li>
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</ul>
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