Maximum Depth of Binary Tree

Given a binary tree, find its maximum depth.

The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.

提交的错误，不知道为什么，但是要自己避免。

C++实现代码：

#include<iostream>
#include<new>
#include<vector>
#include<stack>
using namespace std;

//Definition for binary tree
struct TreeNode
{
int val;
TreeNode *left;
TreeNode *right;
TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

class Solution
{
public:
int maxDepth(TreeNode *root)
{
if(root)
{
if(root->left==NULL&&root->right==NULL)
return 1;
int leftDepth=maxDepth(root->left);
int rightDepth=maxDepth(root->right);
return leftDepth>= rightDepth ?(leftDepth+1):(rightDepth+1);
}
return 0;
}
void createTree(TreeNode *&root)
{
int i;
cin>>i;
if(i!=0)
{
root=new TreeNode(i);
if(root==NULL)
return;
createTree(root->left);
createTree(root->right);
}
}
};

int main()
{
Solution s;
TreeNode *root;
s.createTree(root);
cout<<s.maxDepth(root);
cout<<endl;
}