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# 0965. Univalued Binary Tree

<https://leetcode.com/problems/univalued-binary-tree>

## Description

A binary tree is **uni-valued** if every node in the tree has the same value.

Given the `root` of a binary tree, return `true` *if the given tree is **uni-valued**, or* `false` *otherwise.*

**Example 1:**

![](https://assets.leetcode.com/uploads/2018/12/28/unival_bst_1.png)

```
**Input:** root = [1,1,1,1,1,null,1]
**Output:** true
```

**Example 2:**

![](https://assets.leetcode.com/uploads/2018/12/28/unival_bst_2.png)

```
**Input:** root = [2,2,2,5,2]
**Output:** false
```

**Constraints:**

* The number of nodes in the tree is in the range `[1, 100]`.
* `0 <= Node.val < 100`

## ac

```java
```