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24 lines
834 B
HTML
24 lines
834 B
HTML
<p>Given an integer <code>n</code>, return <em><code>true</code> if it is a power of four. Otherwise, return <code>false</code></em>.</p>
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<p>An integer <code>n</code> is a power of four, if there exists an integer <code>x</code> such that <code>n == 4<sup>x</sup></code>.</p>
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<p> </p>
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<p><strong>Example 1:</strong></p>
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<pre><strong>Input:</strong> n = 16
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<strong>Output:</strong> true
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</pre><p><strong>Example 2:</strong></p>
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<pre><strong>Input:</strong> n = 5
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<strong>Output:</strong> false
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</pre><p><strong>Example 3:</strong></p>
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<pre><strong>Input:</strong> n = 1
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<strong>Output:</strong> true
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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>-2<sup>31</sup> <= n <= 2<sup>31</sup> - 1</code></li>
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</ul>
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<p> </p>
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<strong>Follow up:</strong> Could you solve it without loops/recursion? |