Project Notes

Construct Binary Tree from Inorder and Postorder Traversal

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Description

tab: English
 
<p>Given two integer arrays <code>inorder</code> and <code>postorder</code> where <code>inorder</code> is the inorder traversal of a binary tree and <code>postorder</code> is the postorder traversal of the same tree, construct and return <em>the binary tree</em>.</p>
 
<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/02/19/tree.jpg" style="width: 277px; height: 302px;" />
<pre>
<strong>Input:</strong> inorder = [9,3,15,20,7], postorder = [9,15,7,20,3]
<strong>Output:</strong> [3,9,20,null,null,15,7]
</pre>
 
<p><strong class="example">Example 2:</strong></p>
 
<pre>
<strong>Input:</strong> inorder = [-1], postorder = [-1]
<strong>Output:</strong> [-1]
</pre>
 
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
 
<ul>
	<li><code>1 &lt;= inorder.length &lt;= 3000</code></li>
	<li><code>postorder.length == inorder.length</code></li>
	<li><code>-3000 &lt;= inorder[i], postorder[i] &lt;= 3000</code></li>
	<li><code>inorder</code> and <code>postorder</code> consist of <strong>unique</strong> values.</li>
	<li>Each value of <code>postorder</code> also appears in <code>inorder</code>.</li>
	<li><code>inorder</code> is <strong>guaranteed</strong> to be the inorder traversal of the tree.</li>
	<li><code>postorder</code> is <strong>guaranteed</strong> to be the postorder traversal of the tree.</li>
</ul>
 
 
 
---
 
[submissions](https://leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/submissions/) | [solutions](https://leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/solutions/)
 
 
tab: 中文
 
<p>给定两个整数数组 <code>inorder</code> 和 <code>postorder</code> ，其中 <code>inorder</code> 是二叉树的中序遍历， <code>postorder</code> 是同一棵树的后序遍历，请你构造并返回这颗&nbsp;<em>二叉树</em>&nbsp;。</p>
 
<p>&nbsp;</p>
 
<p><strong>示例 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/02/19/tree.jpg" />
<pre>
<b>输入：</b>inorder = [9,3,15,20,7], postorder = [9,15,7,20,3]
<b>输出：</b>[3,9,20,null,null,15,7]
</pre>
 
<p><strong>示例 2:</strong></p>
 
<pre>
<b>输入：</b>inorder = [-1], postorder = [-1]
<b>输出：</b>[-1]
</pre>
 
<p>&nbsp;</p>
 
<p><strong>提示:</strong></p>
 
<ul>
	<li><code>1 &lt;= inorder.length &lt;= 3000</code></li>
	<li><code>postorder.length == inorder.length</code></li>
	<li><code>-3000 &lt;= inorder[i], postorder[i] &lt;= 3000</code></li>
	<li><code>inorder</code>&nbsp;和&nbsp;<code>postorder</code>&nbsp;都由 <strong>不同</strong> 的值组成</li>
	<li><code>postorder</code>&nbsp;中每一个值都在&nbsp;<code>inorder</code>&nbsp;中</li>
	<li><code>inorder</code>&nbsp;<strong>保证</strong>是树的中序遍历</li>
	<li><code>postorder</code>&nbsp;<strong>保证</strong>是树的后序遍历</li>
</ul>
 
 
 
---
 
[提交记录](https://leetcode.cn/problems/construct-binary-tree-from-inorder-and-postorder-traversal/submissions/) | [题解](https://leetcode.cn/problems/construct-binary-tree-from-inorder-and-postorder-traversal/solution/)

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