mirror of
https://gitee.com/coder-xiaomo/leetcode-problemset
synced 2025-11-04 19:53:12 +08:00
42 lines
2.1 KiB
HTML
42 lines
2.1 KiB
HTML
<p>Given the <code>root</code> of a binary tree, replace the value of each node in the tree with the <strong>sum of all its cousins' values</strong>.</p>
|
|
|
|
<p>Two nodes of a binary tree are <strong>cousins</strong> if they have the same depth with different parents.</p>
|
|
|
|
<p>Return <em>the </em><code>root</code><em> of the modified tree</em>.</p>
|
|
|
|
<p><strong>Note</strong> that the depth of a node is the number of edges in the path from the root node to it.</p>
|
|
|
|
<p> </p>
|
|
<p><strong class="example">Example 1:</strong></p>
|
|
<img alt="" src="https://assets.leetcode.com/uploads/2023/01/11/example11.png" style="width: 571px; height: 151px;" />
|
|
<pre>
|
|
<strong>Input:</strong> root = [5,4,9,1,10,null,7]
|
|
<strong>Output:</strong> [0,0,0,7,7,null,11]
|
|
<strong>Explanation:</strong> The diagram above shows the initial binary tree and the binary tree after changing the value of each node.
|
|
- Node with value 5 does not have any cousins so its sum is 0.
|
|
- Node with value 4 does not have any cousins so its sum is 0.
|
|
- Node with value 9 does not have any cousins so its sum is 0.
|
|
- Node with value 1 has a cousin with value 7 so its sum is 7.
|
|
- Node with value 10 has a cousin with value 7 so its sum is 7.
|
|
- Node with value 7 has cousins with values 1 and 10 so its sum is 11.
|
|
</pre>
|
|
|
|
<p><strong class="example">Example 2:</strong></p>
|
|
<img alt="" src="https://assets.leetcode.com/uploads/2023/01/11/diagram33.png" style="width: 481px; height: 91px;" />
|
|
<pre>
|
|
<strong>Input:</strong> root = [3,1,2]
|
|
<strong>Output:</strong> [0,0,0]
|
|
<strong>Explanation:</strong> The diagram above shows the initial binary tree and the binary tree after changing the value of each node.
|
|
- Node with value 3 does not have any cousins so its sum is 0.
|
|
- Node with value 1 does not have any cousins so its sum is 0.
|
|
- Node with value 2 does not have any cousins so its sum is 0.
|
|
</pre>
|
|
|
|
<p> </p>
|
|
<p><strong>Constraints:</strong></p>
|
|
|
|
<ul>
|
|
<li>The number of nodes in the tree is in the range <code>[1, 10<sup>5</sup>]</code>.</li>
|
|
<li><code>1 <= Node.val <= 10<sup>4</sup></code></li>
|
|
</ul>
|