Maximum Depth of Binary Tree


Given a binary tree, find its maximum depth.
The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
class Solution {
public:
    int maxDepth(TreeNode *root) {
        if(root == NULL) return 0;
        else return max(maxDepth(root->left)+1, maxDepth(root->right)+1);
    }
};

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