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27 lines
924 B
HTML
27 lines
924 B
HTML
<p>Given the <code>head</code> of a singly linked list, return <code>true</code> if it is a palindrome.</p>
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<p> </p>
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<p><strong>Example 1:</strong></p>
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<img alt="" src="https://assets.leetcode.com/uploads/2021/03/03/pal1linked-list.jpg" style="width: 422px; height: 62px;" />
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<pre>
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<strong>Input:</strong> head = [1,2,2,1]
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<strong>Output:</strong> true
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</pre>
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<p><strong>Example 2:</strong></p>
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<img alt="" src="https://assets.leetcode.com/uploads/2021/03/03/pal2linked-list.jpg" style="width: 182px; height: 62px;" />
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<pre>
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<strong>Input:</strong> head = [1,2]
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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>The number of nodes in the list is in the range <code>[1, 10<sup>5</sup>]</code>.</li>
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<li><code>0 <= Node.val <= 9</code></li>
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</ul>
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<p> </p>
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<strong>Follow up:</strong> Could you do it in <code>O(n)</code> time and <code>O(1)</code> space? |