LeetCode: 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.

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Use a recursive call. The maximum depth is the maximum depth of its left subtree and right subtree plus 1.

C++ Code:

/*
 * func: max_depth
 * goal: find the max depth of the given binary tree
 * @param root: root node of the tree
 * return: maximum depth
 */
int max_depth(TreeNode *root){
    if(root == nullptr){
        return 0;
    }
    else{
        return std::max(max_depth(root->left), max_depth(root->right)) + 1;
    }
}

Python Code:

# func: find the maximum depth of binary tree
# @param root: root node of the tree
# @return: maximum depth
def max_depth(root):
    if not root:
        return 0
    else:
        return max(max_depth(root.left), max_depth(root.right)) + 1