class Solution { public: int maxDepth(TreeNode* root) { int deep = 0; bianli(deep, root); return max_; } void bianli(int &deep, TreeNode* root) { if (root == nullptr) { return; } deep++; if (deep > max_) { max_ = deep; } if (root->left != nullptr) { bianli(deep, root->left); deep--; } i...