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28 lines
978 B
HTML
28 lines
978 B
HTML
<p>A <a href="https://en.wikipedia.org/wiki/Perfect_number" target="_blank"><strong>perfect number</strong></a> is a <strong>positive integer</strong> that is equal to the sum of its <strong>positive divisors</strong>, excluding the number itself. A <strong>divisor</strong> of an integer <code>x</code> is an integer that can divide <code>x</code> evenly.</p>
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<p>Given an integer <code>n</code>, return <code>true</code><em> if </em><code>n</code><em> is a perfect number, otherwise return </em><code>false</code>.</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> num = 28
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<strong>Output:</strong> true
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<strong>Explanation:</strong> 28 = 1 + 2 + 4 + 7 + 14
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1, 2, 4, 7, and 14 are all divisors of 28.
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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> num = 7
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<strong>Output:</strong> false
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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 <= num <= 10<sup>8</sup></code></li>
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</ul>
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