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35 lines
1.3 KiB
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35 lines
1.3 KiB
HTML
<p>Given the <code>root</code> of an n-ary tree, return <em>the preorder traversal of its nodes' values</em>.</p>
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<p>Nary-Tree input serialization is represented in their level order traversal. Each group of children is separated by the null value (See examples)</p>
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<p> </p>
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<p><strong>Example 1:</strong></p>
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<p><img src="https://assets.leetcode.com/uploads/2018/10/12/narytreeexample.png" style="width: 100%; max-width: 300px;" /></p>
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<pre>
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<strong>Input:</strong> root = [1,null,3,2,4,null,5,6]
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<strong>Output:</strong> [1,3,5,6,2,4]
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</pre>
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<p><strong>Example 2:</strong></p>
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<p><img alt="" src="https://assets.leetcode.com/uploads/2019/11/08/sample_4_964.png" style="width: 296px; height: 241px;" /></p>
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<pre>
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<strong>Input:</strong> root = [1,null,2,3,4,5,null,null,6,7,null,8,null,9,10,null,null,11,null,12,null,13,null,null,14]
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<strong>Output:</strong> [1,2,3,6,7,11,14,4,8,12,5,9,13,10]
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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 tree is in the range <code>[0, 10<sup>4</sup>]</code>.</li>
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<li><code>0 <= Node.val <= 10<sup>4</sup></code></li>
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<li>The height of the n-ary tree is less than or equal to <code>1000</code>.</li>
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</ul>
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<p> </p>
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<p><strong>Follow up:</strong> Recursive solution is trivial, could you do it iteratively?</p>
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