Solution (leetcode-in-java 1.21 API)

java.lang.Object
- g0901_1000.s0968_binary_tree_cameras.Solution

```
public class Solution
extends Object
```
968 - Binary Tree Cameras.
Hard

You are given the root of a binary tree. We install cameras on the tree nodes where each camera at a node can monitor its parent, itself, and its immediate children.

Return the minimum number of cameras needed to monitor all nodes of the tree.

Example 1:

Input: root = [0,0,null,0,0]

Output: 1

Explanation: One camera is enough to monitor all nodes if placed as shown.

Example 2:

Input: root = [0,0,null,0,null,0,null,null,0]

Output: 2

Explanation: At least two cameras are needed to monitor all nodes of the tree. The above image shows one of the valid configurations of camera placement.

Constraints:
- The number of nodes in the tree is in the range [1, 1000].
- Node.val == 0

- Constructor Summary
  
  Constructors
  Constructor Description
  
  Solution()
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  int minCameraCover(TreeNode root)
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- Solution
```
public Solution()
```

Method Detail

minCameraCover

public int minCameraCover(TreeNode root)