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35 lines
1.0 KiB
HTML
35 lines
1.0 KiB
HTML
<p>Given the <code>head</code> of a singly linked list, reverse the list, and return <em>the reversed list</em>.</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/2021/02/19/rev1ex1.jpg" style="width: 542px; height: 222px;" />
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<pre>
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<strong>Input:</strong> head = [1,2,3,4,5]
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<strong>Output:</strong> [5,4,3,2,1]
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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/2021/02/19/rev1ex2.jpg" style="width: 182px; height: 222px;" />
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<pre>
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<strong>Input:</strong> head = [1,2]
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<strong>Output:</strong> [2,1]
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</pre>
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<p><strong>Example 3:</strong></p>
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<pre>
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<strong>Input:</strong> head = []
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<strong>Output:</strong> []
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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 the range <code>[0, 5000]</code>.</li>
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<li><code>-5000 <= Node.val <= 5000</code></li>
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</ul>
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<p> </p>
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<p><strong>Follow up:</strong> A linked list can be reversed either iteratively or recursively. Could you implement both?</p>
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