968. Binary Tree Cameras

LeetCodeDynamic ProgrammingTreeDepth-First SearchBinary TreeOpen on judge ↗

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 =

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solution.cppC++17

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