剑指offer——60二叉树的深度

 1 class Solution {
 2 public:
 3     int TreeDepth(TreeNode* pRoot)
 4     {
 5         if (pRoot == nullptr)return 0;
 6         //深度优先遍历
 7         DFS(pRoot, 1);
 8         return maxLevel;
 9     }
10 
11 private:
12     int maxLevel = -1;
13     void DFS(TreeNode *pRoot, int level)
14     {
15         if (pRoot == nullptr)return;
16         maxLevel = maxLevel > level ? maxLevel : level;
17         DFS(pRoot->left, level + 1);
18         DFS(pRoot->right, level + 1);
19     }    
20 };