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50 lines
1.4 KiB
HTML
50 lines
1.4 KiB
HTML
<p>You are given an integer <code>n</code>.</p>
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<p>Return the <strong>largest <span data-keyword="prime-number">prime number</span></strong> less than or equal to <code>n</code> that can be expressed as the <strong>sum</strong> of one or more <strong>consecutive prime numbers</strong> starting from 2. If no such number exists, return 0.</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">n = 20</span></p>
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<p><strong>Output:</strong> <span class="example-io">17</span></p>
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<p><strong>Explanation:</strong></p>
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<p>The prime numbers less than or equal to <code>n = 20</code> which are consecutive prime sums are:</p>
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<ul>
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<li>
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<p><code>2 = 2</code></p>
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</li>
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<li>
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<p><code>5 = 2 + 3</code></p>
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</li>
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<li>
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<p><code>17 = 2 + 3 + 5 + 7</code></p>
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</li>
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</ul>
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<p>The largest is 17, so it is the answer.</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">n = 2</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>The only consecutive prime sum less than or equal to 2 is 2 itself.</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 <= n <= 5 * 10<sup>5</sup></code></li>
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</ul>
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