> For the complete documentation index, see [llms.txt](https://nataliekung.gitbook.io/solutions/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://nataliekung.gitbook.io/solutions/maximum_depth_of_binary_tree.md).

# Maximum Depth of Binary Tree

int maxDepth(TreeNode\* root) {

if(!root) return 0;

if(!root->left)//必须是leaf

return maxDepth(root->right)+1;

if(!root->right)

return maxDepth(root->left)+1;

return 1+max(maxDepth(root->left),maxDepth(root->right));

}