题解 | #二叉树的最大深度#

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--;
        }

        if (root->right != nullptr) {
            bianli(deep, root->right);
            deep--;
        }
    }
    int max_ = 0;
};