leetcode 每日一题 104. Maximum Depth of Binary Tree

class Solution {
public:
int count=0;
int maxDepth(TreeNode* root) {
if(root==NULL) return 0;
count=max(maxDepth(root->left),maxDepth(root->right));
return count+1;
}
};

int maxDepth(TreeNode *root) {
// Start typing your C/C++ solution below
// DO NOT write int main() function
if(root == NULL) return 0;
queue<TreeNode*> que;
que.push(root);
int count = 1;
int depth = 0;
while(!que.empty())
{
TreeNode* tmp = que.front();
que.pop();
count--;

if(tmp->left)
que.push(tmp->left);
if(tmp->right)
que.push(tmp->right);
if(count == 0)
{
depth++;
count=que.size();
}
}
return depth;
}