二叉树的深度

class Solution {
public:
int TreeDepth(TreeNode* pRoot)
{
int leftDepth, rightDepth;
if(pRoot == NULL) return 0;
else
{
leftDepth = TreeDepth(pRoot->left);
rightDepth = TreeDepth(pRoot->right);
return leftDepth > rightDepth? leftDepth + 1:rightDepth + 1;
}
}
};