1
0
mirror of https://gitee.com/coder-xiaomo/leetcode-problemset synced 2025-01-11 02:58:13 +08:00
Code Issues Projects Releases Wiki Activity GitHub Gitee
leetcode-problemset/leetcode-cn/problem (Chinese)/二叉树的前序遍历 [binary-tree-preorder-traversal].html
2022-03-29 12:43:11 +08:00

52 lines
1.3 KiB
HTML
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<p>给你二叉树的根节点 <code>root</code> ,返回它节点值的 <strong>前序</strong><em> </em>遍历。</p>
<p> </p>
<p><strong>示例 1</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/15/inorder_1.jpg" style="width: 202px; height: 324px;" />
<pre>
<strong>输入:</strong>root = [1,null,2,3]
<strong>输出:</strong>[1,2,3]
</pre>
<p><strong>示例 2</strong></p>
<pre>
<strong>输入:</strong>root = []
<strong>输出:</strong>[]
</pre>
<p><strong>示例 3</strong></p>
<pre>
<strong>输入:</strong>root = [1]
<strong>输出:</strong>[1]
</pre>
<p><strong>示例 4</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/15/inorder_5.jpg" style="width: 202px; height: 202px;" />
<pre>
<strong>输入:</strong>root = [1,2]
<strong>输出:</strong>[1,2]
</pre>
<p><strong>示例 5</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/15/inorder_4.jpg" style="width: 202px; height: 202px;" />
<pre>
<strong>输入:</strong>root = [1,null,2]
<strong>输出:</strong>[1,2]
</pre>
<p> </p>
<p><strong>提示:</strong></p>
<ul>
<li>树中节点数目在范围 <code>[0, 100]</code></li>
<li><code>-100 <= Node.val <= 100</code></li>
</ul>
<p> </p>
<p><strong>进阶:</strong>递归算法很简单,你可以通过迭代算法完成吗?</p>