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"content": "<p>Given an n-ary tree, return the <em>level order</em> traversal of its nodes' values.</p>\n\n<p><em>Nary-Tree input serialization is represented in their level order traversal, each group of children is separated by the null value (See examples).</em></p>\n\n<p> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n\n<p><img src=\"https://assets.leetcode.com/uploads/2018/10/12/narytreeexample.png\" style=\"width: 100%; max-width: 300px;\" /></p>\n\n<pre>\n<strong>Input:</strong> root = [1,null,3,2,4,null,5,6]\n<strong>Output:</strong> [[1],[3,2,4],[5,6]]\n</pre>\n\n<p><strong class=\"example\">Example 2:</strong></p>\n\n<p><img alt=\"\" src=\"https://assets.leetcode.com/uploads/2019/11/08/sample_4_964.png\" style=\"width: 296px; height: 241px;\" /></p>\n\n<pre>\n<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]\n<strong>Output:</strong> [[1],[2,3,4,5],[6,7,8,9,10],[11,12,13],[14]]\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li>The height of the n-ary tree is less than or equal to <code>1000</code></li>\n\t<li>The total number of nodes is between <code>[0, 10<sup>4</sup>]</code></li>\n</ul>\n",
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