Class Solution

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:** ![](https://assets.leetcode.com/uploads/2018/12/29/bst_cameras_01.png) **Input:** root = [0,0,null,0,0] **Output:** 1 **Explanation:** One camera is enough to monitor all nodes if placed as shown. **Example 2:** ![](https://assets.leetcode.com/uploads/2018/12/29/bst_cameras_02.png) **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 Details

    • Solution

      public Solution()
  • Method Details

    • minCameraCover

      public int minCameraCover(TreeNode root)