【刷题日记】二叉树-二叉树的最大深度-L104-Easy

class Solution {
public:
    int maxDepth(TreeNode* root) {
        int depth = 0;
        queue<TreeNode*> qe;
        if (root)
            qe.push(root);
        while (!qe.empty())
        {
            int node_num = qe.size();
            for (int i = 0; i < node_num; i++)
            {
                auto tmp = qe.front();
                qe.pop();

                if (tmp->left)
                    qe.push(tmp->left);
                if (tmp->right)
                    qe.push(tmp->right);
            }
            ++depth;
        }

        return depth;
    }
};